The NBA's one-and-done rule is still standing, but what would college basketball teams look like if players had to stay all four years?

Ben Simmons would be a senior at LSU. Lonzo Ball, TJ Leaf and Aaron Holiday would all still be starters at UCLA. And both Duke and Kentucky wouldn't even be able to play all of their McDonald's All-Americans in most games.

Of all the hypothetical offseason topics to consider, this might be the most unrealistic. It's practically a miracle when top-10 recruits stay for more than one season, let alone four. Yet it's one of the more entertaining subjects.

For the most part, we'll look at teams that are already expected to be good this season. Maybe Florida State's potential increases from the second round of the NCAA tournament to the Elite Eight with the re-insertion of Malik Beasley, Dwayne Bacon and Jonathan Isaac. Perhaps UCLA jumps from "Sweet 16 good" to "Final Four great."

But there is one squad that surges from "might not make the tournament" to "could win the whole thing" with its adjusted roster. Thoughts and prayers to that fanbase for the upcoming reminder of what could have been.

Two rules of thumb to keep in mind before you go arguing about a certain team or player:

• We must assume that all recruits still would have made the same decisions, because it would be impossible to play the trickle-down-effect game to determine where players would have signed.
• Transfers still count. Thus, Kansas would have Malik Newman and Dedric Lawson, Villanova would have Eric Paschall, and about 2,000 other transfers over the past three years would have happened.

In other words, all teams would have their current rosters plus all the players who still would have at least one year of eligibility remaining had they not declared for the draft.

Teams are ranked in ascending order of how good they would be.

Honorable Mentions

In addition to our top 10, here are 10 other teams that get back at least one player and would be in great shape for an Elite Eight run.

Gonzaga Bulldogs

The Zags will be one of the country's five best teams this season, but all they get back in this exercise is Zach Collins. Granted, he would be the perfect addition, since 6'10" Killian Tillie is more of a stretch 4 than a center. However, it's not enough to keep pace with what these other teams are adding.

North Carolina Tar Heels

It's the same story for UNC as it is for Gonzaga. The Heels are already a solid title contender and would get a big man in the form of Tony Bradley, but that's it. Again, this would afford the current three-point-shooting center (Luke Maye) more opportunity to do his thing along the perimeter, but they would still be dependent on Cameron Johnson and Kenny Williams. That's fine for the actual 2018-19 season. However, it wouldn't work out well in a universe where Duke has Gary Trent Jr. and RJ Barrett as reserves.

Syracuse Orange

With Malachi Richardson and Tyler Lydon on the roster, Syracuse was the toughest team to leave out of the top 10. The Orange still have all five starters from last season, and Jalen Carey figures to be a strong contributor as a freshman. That makes for one heck of an eight-man rotation for Jim Boeheim, a coach who never goes much deeper than that anyway.

Oregon Ducks

Reintroduce Tyler Dorsey and Troy Brown to the backcourt and Oregon is cooking with gas. Led by Bol Bol and Louis King, the Ducks have one of the nation's best recruiting classes. There's not much experience on the roster, but a senior leader such as Dorsey would change that in a big way. Along with Arizona, UCLA and Washington, Oregon would give the Pac-12 a fantastic race for the conference title.

Nevada Wolf Pack

Nevada will be a preseason Top 10 team because guys like Caleb Martin, Cody Martin and Jordan Caroline didn't go pro this past spring. But there is one player the Wolf Pack get back in this exercise: Cameron Oliver. This team is already outrageously versatile, and adding another double-double machine with three-point range would be almost unfair.

Louisville Cardinals

A trip to the 2019 NCAA tournament probably isn't in the Cards, but it would be if Louisville still had Donovan Mitchell, Deng Adel and Ray Spalding. Even though V.J. King is the only returning player who averaged at least 16.0 minutes or 6.2 points per game last year, that threesome would make the Cardinals a legitimate threat.

Maryland Terrapins

No, the Terps don't get Melo Trimble back, but they would add Diamond Stone, Kevin Huerter and Justin Jackson. Pair that trio with Anthony Cowan Jr., Bruno Fernando and stud freshman Jalen Smith and you've got a strong (albeit shallow) rotation that could contend for a title.

Texas Longhorns

Eric Davis Jr. isn't a noteworthy addition, but Jarrett Allen and Mohamed Bamba are. If those frontcourt titans were still with the Longhorns, they could compete with anyone—even though this would still be one of the country's worst perimeter-shooting teams.

UNLV Rebels

Despite missing the NCAA tournament in each of the past five seasons, UNLV is always a solid candidate for this list—proof that the Rebels are among the best in the nation at wasting potential. Stephen Zimmerman, Brandon McCoy and Derrick Jones Jr. would all return to make up a nearly unstoppable frontcourt.

Michigan Wolverines

It'd be nowhere near as loaded as some of these rosters—let alone the 10 that follow—but Michigan would be more dangerous if it still had Moritz Wagner.

10. Florida State Seminoles

Players Gained: Malik Beasley, Dwayne Bacon, Jonathan Isaac

Starting Five: Trent Forrest, Beasley, Bacon, Terance Mann, Isaac

Top Reserves: Phil Cofer, M.J. Walker, PJ Savoy, Mfiondu Kabengele, Christ Koumadje

Here's one case where the players probably should have stayed for four years.

Beasley, Bacon and Isaac haven't amounted to much in the NBA—particularly Beasley. In theory, he would be the biggest star for the Seminoles, as he shot 38.7 percent from three-point range and averaged 15.6 points per game as a freshman before becoming the No. 19 pick in the 2016 NBA draft. But he has barely been able to crack the Denver Nuggets rotation, starting just one game in his pro career.

Likewise, Bacon has only carved out a minor role, averaging 3.3 points per contest with the Charlotte Hornets in his rookie campaign. Isaac has been better than the two wings, but not by much. All three members of the trio have already spent time in the G League.

Had they remained at Florida State, though, all three might be All-American candidates for this coming season. And if that's the case, we're drastically underselling FSU at No. 10, considering the 'Noles are No. 17 in the preseason AP Top 25 without those three veterans.

It's hard to not love the depth on this roster. Forrest, Mann, Cofer, Walker, Savoy, Kabengele and Koumadje all averaged better than 6.0 points per game last season, so Florida State would have no problems running at least 10 deep.

It's a textbook positionless roster, too, as each significant piece aside from the 7'4" Koumadje stands between 6'4" and 6'10". And though there aren't any three-point assassins present, the majority of the primary 10 has at least some perimeter potential.

9. Washington Huskies

Players Gained: Markelle Fultz, Dejounte Murray, Marquese Chriss

Starting Five: Fultz, Jaylen Nowell, Matisse Thybulle, Noah Dickerson, Chriss

Top Reserves: Murray*, David Crisp, Dominic Green, Nahziah Carter, Sam Timmins

Murray is out for the year with a torn ACL, so we should probably exclude him from Washington's starting lineup.

Even without that defensive specialist, though, the Fultz-led Huskies would be a serious contender for the first time in more than a decade.

Washington was too young during Fultz's lone collegiate season (2016-17). Malik Dime was the only upperclassman who played legitimate minutes, and the team predictably went from bad to horrendous when he missed 11 games due to a broken finger. Aside from Dime and Fultz, the roster was almost entirely sophomores who were still trying to figure out their roles.

Now, however, Thybulle, Dickerson, Chriss, Crisp and Green would all be seniors and playing alongside Fultz in his third season of domination. This team would be an absolute force on offense, and—with head coach Mike Hopkins now running the show—would be a whole heck of a lot better on defense than it was in Fultz's freshman season under Lorenzo Romar.

But in a world where Lonzo Ball, Ben Simmons, Josh Jackson and a combined 21 Duke and Kentucky players are also returning, Fultz and Chriss likely wouldn't be enough to make Washington one of the top candidates to win the title. Thybulle, Dickerson and Co. are better than they were two years ago, but they can't hold a candle to most of the starting wings and forwards in our top eight.

8. LSU Tigers

Players Gained: Ben Simmons, Antonio Blakeney, Brandon Sampson

Starting Five: Tremont Waters, Blakeney, Skylar Mays, Simmons, Naz Reid

Top Reserves: Sampson, Emmitt Williams, Ja'Vonte Smart, Kavell Bigby-Williams, Daryl Edwards, Wayde Sims

Simmons averaged 19.2 points, 11.8 rebounds, 4.8 assists and 2.0 steals per game as a freshman on a 2015-16 roster that didn't have much else worth mentioning.

Imagine what he could've done as a senior.

Simmons single-handedly made it tempting to put LSU as high as No. 3 on this list. Given how well he has performed in the NBA, it's impossible to put a limit on what he could be doing in a fourth season against college competition. Wilt Chamberlain averaged 29.9 points and 18.3 rebounds in his two seasons with Kansas in the 1950s, and it's reasonable to think Simmons could do something similar.

Waters would be a glorious second fiddle, giving the Tigers one of the best inside-outside attacks ever assembled. But the rest of the supporting cast leaves much to be desired—at least compared to the hypothetical starting lineups ahead.

Blakeney was never an efficient scorer, and he didn't do much aside from shoot it while he was on the floor. Mays is in a similar boat, though at least he played some defense and occasionally passed to open teammates. And while Reid is a highly touted freshman, he's nowhere near the instant-impact guarantee Simmons was from day one, and he would be overmatched by most of the frontcourts in our top 10.

Those players aren't bad at all, but they have more glaring red flags than most of the remaining starters.

Still, LSU would be a problem for opponents and likely destined for a top-three seed in the NCAA tournament for the first time since 1981. And with Simmons' status as arguably the best player in the country, anything would be possible in the single-elimination tourney we all know and love.

7. Villanova Wildcats

Players Gained: Jalen Brunson, Mikal Bridges, Omari Spellman, Donte DiVincenzo

Starting Five: Brunson, DiVincenzo, Bridges, Eric Paschall, Spellman

Top Reserves: Phil Booth, Collin Gillespie, Dhamir Cosby-Roundtree, Joe Cremo, Jahvon Quinerly, Cole Swider, Brandon Slater

Though Villanova wouldn't get back any stars who have been gone for multiple years, the Wildcats didn't have a senior in their primary rotation last season. That not only means they'd have everyone who played a key part in the 2018 national championship, but they'd also add an excellent three-point shooter from Albany (Cremo) and a trio of top-60 recruits.

That's not a lot of star power as far as NBA players and potential are concerned, but that is one heck of a 12-man college rotation. It's hard to make complaints about a team that already had one of the highest adjusted efficiency margins of the KenPom era, which dates back to 2002.

But here's one: Could this frontcourt hang with any of the squads in our top six?

The three-point shot is basketball's great equalizer, and Villanova spreads the floor as well as any team. It works like a charm in the real world, as almost every squad has, at most, one dominant big man. The Wildcats might lose the rebounding battle or allow a few too many easy buckets because of that opposing post presence, but they can more than counterbalance that with perimeter shooting.

In this exercise, though, they might need to contend with an Arizona frontcourt that features Deandre Ayton and Lauri Markkanen, or a Duke frontcourt with the likes of Marvin Bagley III, Wendell Carter Jr., Zion Williamson and Brandon Ingram. If those teams pound the paint, they could have a field day against Paschall and Spellman.

All the same, it's a testament to the job Jay Wright has done at Villanova that the Wildcats could at least put up a fight against the Arizonas and Dukes that are getting back a bunch of one-and-done guys. Two national championships in three seasons without a player who will be a full-time NBA starter in the immediate future is remarkable.

6. Arizona Wildcats

Players Gained: Deandre Ayton, Lauri Markkanen, Allonzo Trier, Rawle Alkins, Kobi Simmons, Chance Comanche

Starting Five: Brandon Williams, Alkins, Trier, Markkanen, Ayton

Top Reserves: Simmons, Comanche, Emmanuel Akot, Ira Lee, Brandon Randolph, Dylan Smith, Chase Jeter, Alex Barcello, Justin Coleman, Ryan Luther

This one will hurt the Arizona fans who have had to endure a long offseason of predictions that the Wildcats might not even be good enough to make the NCAA tournament.

Every other team in our top 10 will open the season in the AP Top 25. They are merely going from good to great—or from great to elite—by adding former early entrants. But Arizona would transform from mediocre to sensational by getting these six players back.

How much fun would a starting frontcourt of Markkanen and Ayton be? We've seen plenty of teams with one stretch 5 in recent years, but two seven-footers with legitimate three-point range, one of which (Ayton) could outmuscle anyone in the country with his chiseled frame? That's unfair. Factor in two excellent scoring, driving guards in Trier and Alkins and there's no way to stop this offense from putting up points.

Even Simmons and Comanche would be key contributors. Neither one was valuable by the end of the 2016-17 season, but they were highly touted recruits who were stuck behind better, more experienced players. By this point, they would rank among the country's best reserves.

The massive question mark is point guard.

Both Trier and Alkins dropped dimes occasionally, but that's not their specialty. The Wildcats would instead need to bank on either Samford transfer Coleman or true freshman Williams to run the offense—which could be problematic against the likes of Brunson, Lonzo Ball or De'Aaron Fox.

But compared to the red flags all over the roster this season, Arizona fans would gladly live with that possible Achilles' heel on this Final Four-worthy team.

5. Michigan State Spartans

Players Gained: Deyonta Davis, Jaren Jackson Jr., Miles Bridges

Starting Five: Cassius Winston, Joshua Langford, Bridges, Davis, Jackson

Top Reserves: Nick Ward, Matt McQuaid, Kenny Goins, Xavier Tillman, Marcus Bingham

Michigan State enters the 2018-19 season with major question marks in the frontcourt.

Ward is the clear leader, but can he play more than 20 minutes per game and remain as efficient? Beyond that, the Spartans are left to hope that Tillman breaks out as a sophomore and/or Bingham immediately excels, even though he wasn't a top-60 recruit.

But if the Spartans bring back Davis, Jackson and Bridges, goodness gracious, best of luck scoring in the paint or rebounding against that team.

Thanks in large part to Jackson and Ward, Michigan State led the nation in both block percentage and two-point field-goal defense last season. To that tandem, the Spartans would add Davis as a senior. Considering he averaged 11.8 rebounds and 3.9 blocks per 40 minutes as a freshman, he would probably be the anchor of this top-notch defense.

Bridges was no slouch on D, either, but his offensive impact would make Michigan State one of the few legitimate candidates to win the national championship. When he was healthy—and especially when he was feeling it from distance—Bridges was one of the most unguardable players in the country over the past two seasons.

Along with those forwards, Sparty has excellent guards. Most noteworthy among them is Winston, who averaged 6.9 assists while shooting 49.7 percent from three-point range last year. There aren't many players who are more lethal with the ball in their hands. The 6'1" guard is one of the smallest guys on the roster, but he's the biggest reason Michigan State is expected to win the Big Ten.

If this team had a little more quality depth, it would rank in the top five. Ward and McQuaid would be great reserves, but comparing Goins and Tillman to the eighth-best and ninth-best options on the top teams isn't a fair battle.

4. UCLA Bruins

Players Gained: Lonzo Ball, TJ Leaf, Aaron Holiday, Ike Anigbogu

Starting Five: Ball, Holiday, Kris Wilkes, Leaf, Moses Brown

Top Reserves: Jaylen Hands, Anigbogu, Prince Ali, Jules Bernard, Tyger Campbell, David Singleton, Alex Olesinski, Cody Riley, Jalen Hill, Chris Smith

Ball as a junior.

Need we say more?

It still blows my mind that Ball never recorded a triple-double as a freshman at UCLA, but he would probably be averaging one by now—especially with this much talent around him.

Ball is one of five former McDonald's All-Americans on this roster. Leaf played with Ball in the 2016 game. Both Wilkes and Hands participated in 2017, and Brown was the Bruins' representative this past March.

Holiday is the only starter who doesn't fit that description, but he averaged 20.3 points and 5.8 assists per game while shooting 42.9 percent from three-point range last year. The senior wouldn't exactly be a weak link in a starting lineup capable of scoring at will against anyone.

What about the defense, though?

Brown gives UCLA the shot-blocking presence it has been missing for more than a decade, but the defense has been awful as a whole for several years. Unless Brown is the second coming of Emeka Okafor, one big man won't be enough to fix all of the Bruins' problems on that end.

But if that just means they have to win games played in the triple digits, so be it. With this much depth, UCLA would have no problem with playing in repeated track meets.

3. Kansas Jayhawks

Players Gained: Josh Jackson, Malik Newman, Cheick Diallo

Starting Five: Charlie Moore, Newman, Jackson, Dedric Lawson, Udoka Azubuike

Top Reserves: Quentin Grimes, Diallo, Lagerald Vick, Devon Dotson, David McCormack, K.J. Lawson, Silvio De Sousa, Marcus Garrett, Mitch Lightfoot

As is, Kansas is one of the top candidates to win the 2019 national championship—if not the preseason favorite. Since Vick and Azubuike stayed another year, Moore and the Lawsons transferred into the program and three top-40 freshmen headed to Lawrence, the Jayhawks are all sorts of stacked.

Plug Jackson, Newman and Diallo back into that mix and this is easily the closest any team has come to knocking Duke or Kentucky out of the top two of this hypothetical ranking in the past four years.

Jackson is the main draw. We've seen with the Phoenix Suns that he's still a liability at the free-throw line and a subpar three-point shooter, but can you imagine the impact he would have as a junior given all he did as a freshman? He'd be right up there with Ben Simmons, Brandon Ingram and Jamal Murray on the list of player of the year candidates.

With the exception of Eric Paschall (Fordham) as Villanova's fifth-best starter, Kansas is the only team in our top 10 with a transfer in its starting lineup. And the Jayhawks have three of them in Moore (California), Newman (Mississippi State) and Dedric Lawson (Memphis).

Lawson is Kansas's 2019 Wooden Award candidate, but Moore might be the most important player to this team's success. Frank Mason III won the Wooden Award in 2017, and Devonte' Graham was one of the five finalists for it this past season. Suffice it to say, Kansas has grown accustomed to having an elite lead guard. And if Moore doesn't pan out, the Jayhawks will be forced to start either Grimes or Dotson at point guard. Those are excellent freshmen, but it's still a tough ask of first-year players.

Either way, this team is loaded. Lightfoot is a respectable scorer and rebounder and was one of the better shot blockers in the country last year. He'd be a starter for at least 95 percent of teams, yet he's arguably the 14th-best asset on this roster. That's silly.

2. Duke Blue Devils

Players Gained: Jayson Tatum, Brandon Ingram, Marvin Bagley III, Luke Kennard, Gary Trent Jr., Trevon Duval, Wendell Carter Jr., Harry Giles III, Frank Jackson III

Starting Five: Duval, Kennard, Tatum, Ingram, Bagley

Top Reserves: RJ Barrett, Trent, Cam Reddish, Zion Williamson, Tre Jones, Carter, Giles, Jackson, Joey Baker, Marques Bolden, Alex O'Connell

Duke's frontcourt depth is ridiculous.

Barrett, Reddish and Williamson are three of the top incoming freshmen in the country and mortal locks to declare for the NBA draft after one season, but not one of those forwards would even be a starter with Tatum, Ingram and Bagley all in the mix. Even if Giles were healthy enough to play, he'd probably be the eighth-best forward/center on this roster.

However, if you've been paying attention to Duke for the past few years, it should come as no surprise that point guard is a gigantic question mark.

Grayson Allen led the Blue Devils in assists in 2016 and 2017 and wasn't far behind Duval for the team lead this past season, but he was always more of a scorer than a facilitator. He just got dimes because no one else could run the offense. And Allen graduated this past spring and isn't eligible to rejoin Duke in this exercise.

We're putting Duval as the starting point guard and assuming he'd have the good sense to be a pass-first leader and never take another jump shot. You could also make a strong case for Jones. Really, the Blue Devils might be best off with Kennard at point guard and Barrett in the starting lineup, but there would still be minor backcourt concerns no matter the combination.

It wouldn't stop them from defeating all of the teams below them on the list, but that lead guard dilemma is the main reason Duke falls behind Kentucky in the race for the top spot. There's no question you want this frontcourt situation over that of the Wildcats, but Kentucky's veteran guards take the cake.

1. Kentucky Wildcats

Players Gained: Malik Monk, Jamal Murray, De'Aaron Fox, Bam Adebayo, Skal Labissiere, Isaiah Briscoe, Shai Gilgeous-Alexander, Kevin Knox, Hamidou Diallo, Wenyen Gabriel, Isaac Humphries, Jarred Vanderbilt

Starting Five: Fox, Monk, Murray, Adebayo, Labissiere

Top Reserves: Knox, Gilgeous-Alexander, Briscoe, Vanderbilt, Diallo, Gabriel, PJ Washington, Nick Richards, Quade Green, EJ Montgomery, Reid Travis, Ashton Hagans, Keldon Johnson, Immanuel Quickley, Tyler Herro, Humphries

The starting five is phenomenal. Maybe No. 2 Duke could give UK's starters a run for their money, but even No. 3 Kansas would get obliterated by this lineup.

The lone question mark some might have is Labissiere, as his only season in Lexington was a gigantic bust. But he would be a senior, and his game has developed a bit over the last two seasons in the NBA. It's safe to assume he'd be star college center.

Even if Labissiere is the weak link, that Fox-Monk-Murray backcourt would be a destroyer of worlds.

As has been the case in previous seasons, the most entertaining part of this exercise was trying to figure out which "hockey lines" would work best for Kentucky. Here's my proposal:

• First Line: Fox, Diallo, Johnson, Travis, Montgomery
• Second Line: Quickley, Monk, Briscoe, Washington, Adebayo
• Third Line: Green, Murray, Herro, Vanderbilt, Richards
• Fourth Line: Gilgeous-Alexander, Hagans, Knox, Gabriel, Labissiere

Each line has a solid ball-handler, at least one true freshman, a pair of big men and some three-point shooting. Pick any one of these groups and it would rank no worse than seventh on this list. Combine them into one roster and it's hard to argue that anyone else even has a shot.

Kerry Miller covers men's college basketball and college football for Bleacher Report. You can follow him on Twitter, @kerrancejames. Recruit rankings provided by 247Sports.