The gap between spring camp and fall camp in the college football calendar can feel like an eternity to most fans, but the start of June means the regular season begins in less than three months. September will be here before you know it, and with it will come an abundance of important, entertaining nonconference games.

Brace yourself for an inordinate amount of Notre Dame on this list. After spending the bizarre 2020 season as a part-time member of the ACC, the Fighting Irish are returning to their independent ways with four games against opponents likely to open the season ranked in the AP Top 20.

There's plenty of quality action outside South Bend, though.

Week 1 will feature a pair of massive ACC/SEC clashes, as well as what should be an extremely rare ranked battle between the Sun Belt and Big 12.

For Week 2, it'll be a pair of Rose-y Big Ten/Pac-12 showdowns, plus the biggest game in Cy-Hawk Series history.

For Week 3, could we interest you in a "2020 Breakout Special" between Cincinnati and Indiana? If not, how about Nebraska at Oklahoma in what used to be a Big 12 rivalry between two of the 10 best programs in CFB history?

Trust us when we say you won't be bored in September. But if you can only pick a couple of games to watch this fall, we've ranked the top nonconference matchups by how much you will be kicking yourself if you miss them.

Honorable Mentions

We weren't given the opportunity to watch many nonconference games in 2020, which means eight will barely whet our ravenous appetite for the upcoming fall. Thus, let's begin by pointing out nine others (in chronological order) that were considered for the list.

Boise State at UCF (Sept. 2)

What a fun Thursday night offering to open the season. Boise State and UCF have never faced each other, but it sure feels like we've been talking about them concurrently for the past few years as teams jostling for the Group of Five's spot in the New Year's Six bowls. Most expect that honor to go to Cincinnati for a second consecutive season, but the winner of this game will vault into the conversation.

LSU at UCLA (Sept. 4)

At long last, Chip Kelly's offensive genius started to shine through last season, his third at UCLA. The Bruins went 3-4, but they averaged better than 35 points per game, and the four losses were by a combined 15 points. They could be a breakout team, or they might get hammered by an LSU squad that is attempting to bounce back from one of the worst title defenses ever. Several bigger games are scheduled for the first Saturday of September, but this one could be a gem.

Washington at Michigan (Sept. 11)

Washington will enter the year as a sexy sleeper for the College Football Playoff. The Huskies will likely debut behind both Oregon and USC in the AP rankings, but they don't face USC or Utah, and they get each of Arizona State, Oregon and UCLA at home. Win this road game against Michigan, and the "UW Undefeated Watch" can officially commence. Also, lose this home game, and the "Fire Jim Harbaugh Watch" can officially continue in earnest.

Texas A&M vs. Colorado (in Denver) (Sept. 11)

Haters love to harp on Alabama's weak nonconference schedule every year, but Texas A&M has the biggest cream puff buffet of any 2021 CFP contender. Aside from this "neutral-site" game against what is expected to be one of the worst teams in the Pac-12, the Aggies have home games against Kent State, New Mexico and Prairie View A&M. In other words, this is the one non-SEC opponent that might hang around for at least a quarter.

Nebraska at Oklahoma (Sept. 18)

Scott Frost has yet to produce a winning season in three years as Nebraska's coach, but a marquee road win over this former Big 12 rival would help fans forget the many bumps in the road. For Oklahoma, this is the only nonconference game that could pose a problem.

Auburn at Penn State (Sept. 18)

In any of the previous four summers, this would have been highlighted as a top clash, as both Auburn and Penn State opened each of the last four seasons ranked No. 16 or better in the AP poll. Neither figures to fit that description this year, but this should be a solid Big Ten/SEC showdown all the same. In fact, this will be the only regular-season meeting between those conferences.

Notre Dame vs. Wisconsin (in Chicago) (Sept. 25)

Independent Notre Dame has four major clashes on its 2021 schedule, and we couldn't rank them all. This is one heck of an honorable mention, though. Notre Dame's new quarterback, Jack Coan, started every game for Wisconsin in 2019.

Army at Wisconsin (Oct. 16)

Each of these programs has more than 125 years of history dating back to the 1890s, but they have somehow never faced each other. Wisconsin figures to be heavily favored, but Army nearly pulled off massive upsets of Oklahoma and Michigan in 2018 and 2019, respectively.

Liberty at Ole Miss (Nov. 6)

Any nonconference game worth a darn in November is a rare treat, but this one should be fun on multiple levels. Expect many, many points, as well as no love lost between Ole Miss fans and their former head coach, current Liberty head coach Hugh Freeze.

8. Louisiana at Texas (Sept. 4)

Four years ago, Tom Herman's tenure as head coach of Texas got out to a rocky start with a home loss to Maryland. The Longhorns won bowl games in each of his four seasons, including the Sugar Bowl after the 2018 campaign, yet it felt like he was forever trying to dig his way out of that initial hole.

Can Steve Sarkisian avoid a similar fate against what might be the best Group of Five team this year?

Billy Napier just led Louisiana to a 10-1 record, the lone loss coming on a last-second field goal against a Coastal Carolina squad that didn't suffer its first defeat until bowl season. The Ragin' Cajuns opened the year with a statement 31-14 road win over a darn good Iowa State team, and they never slowed down.

In 2021, they bring back nearly everyone from the best team in program history.

Per Athlon Sports, Louisiana had 22 defenders play at least 100 snaps last season, and 21 of them are expected to return this fall. The one who isn't returning (linebacker Joe Dillon) ranked 13th on the team in tackles and didn't record a sack, forced fumble or interception.

The offense is also well intact with dual-threat QB Levi Lewis, his entire starting offensive line and all of his receivers and tight ends still on the roster. The Ragin' Cajuns do need to replace the running back tandem of Elijah Mitchell and Trey Ragas (1,895 total yards from scrimmage and 20 touchdowns in 2020), but between Chris Smith (7.3 yards per carry on 94 career rush attempts) and Texas A&M transfer Jacob Kibodi, they've got options.

The question isn't whether Louisiana will be able to run the ball, but whether it can stifle Bijan Robinson.

Over the final two games of his true freshman season, Robinson carried the ball 19 times for 355 yards, made five receptions for another 88 yards and scored six touchdowns. It's almost unfair that Sarkisian goes straight from coaching Najee Harris to coaching this phenom, and equally unfair that he'll make his 2021 season debut against a defense that allowed at least 120 rushing yards in every game last year. Texas should ride him to victory, but this figures to be a close game.

7. Alabama vs. Miami (in Atlanta) (Sept. 4)

College football's million-dollar question heading into the 2021 season: How healthy is D'Eriq King?

Aside from a forgivable dud in a road game against Clemson, the Houston transfer was outstanding at quarterback for Miami last fall. Prior to the Cheez-It Bowl against Oklahoma State, King was averaging 309.3 combined passing and rushing yards per game, as well as 2.6 touchdowns. He swooped in and deftly led the Hurricanes to one of their best seasons of the past 15 years.

Unfortunately, he suffered a torn ACL in the Cheez-It Bowl—in the same knee where he suffered a torn meniscus late in the 2018 season. Even though all reports in the past five months have suggested he is on track to full availability by the time the season begins, we'll have to wait and see how crisp he looks on Labor Day weekend.

If he's firing on all cylinders, Miami could mess around and win this game against a defending national champion that is replacing more than half its starters.

Per usual, Alabama has an absurd amount of talent. The Crimson Tide have also gotten stronger since the start of the offseason, adding former Ohio State wide receiver Jameson Williams and former Tennessee linebacker Henry To'o To'o via the transfer portal.

However, replacing eight of the top 38 picks in the 2021 NFL draft is a daunting task. This is nowhere near the full roster makeover that LSU endured between the 2019 and 2020 campaigns, but making up for the lost impact of Najee Harris, DeVonta Smith and Pat Surtain II will be a challenge, regardless of how well Alabama does on the recruiting trail year after year.

To be clear, I'm not saying the Crimson Tide don't deserve their status as the preseason favorite to win it all again. By the end of the year, I fully expect them to be great. But they might be vulnerable against a veteran Miami team that also made a few marquee pickups from the transfer portal—receiver Charleston Rambo and cornerback Tyrique Stevenson.

Then again, how many times have you heard "Alabama might be vulnerable early" before? Six times in Nick Saban's 14 years at Alabama, the Crimson Tide have opened the season against a ranked nonconference opponent. They won those six games by an average margin of 23.7 points. Even if King is at 100 percent, this one could get ugly.

6. USC at Notre Dame (Oct. 23)

Many of the games on this list are between teams that rarely face each other, but Notre Dame vs. USC is one of the best, most deeply rooted rivalries (nonconference or not) in college football. With the exception of seasons impacted by either COVID-19 or World War II, the Trojans and Fighting Irish have squared off every fall dating back to 1926.

Over the years, the series has seen plenty of ranked-against-ranked matchups: 33 of them, to be exact. But there has only been one such meeting in the past decade, when No. 13 Notre Dame crushed No. 11 USC 49-14 in 2017.

Who knows how things will play out over the first two months of the season prior to this late October game, but this figures to become the 34th ranked-against-ranked installment of this rivalry, as both sides are likely to debut in the Top 20 of the AP poll.

The big matchup to watch will be USC's Heisman hopeful quarterback Kedon Slovis against the Fighting Irish secondary.

Notre Dame's pass defense was hit or miss in 2020. The Irish clamped down well against the ACC's many bad-to-mediocre offenses, but in three games against teams that made the College Football Playoff (Clemson twice, Alabama once), the Irish allowed 1,058 passing yards (353 per game) and eight touchdowns with one interception.

From that defense, they need to replace first-team AP All-America linebacker Jeremiah Owusu-Koramoah, as well as veteran defensive backs Nick McCloud and Shaun Crawford. It may be a rebuilding year in that back seven, which could be a major problem against the man who led the nation in pass attempts per game last fall.

5. North Carolina at Notre Dame (Oct. 30)

More often than not, at least one preseason Top 10 team crashes and burns, finishing the year unranked. If North Carolina manages to secure that preseason Top 10 status (probable, but not guaranteed), the Tar Heels are the most likely candidate to play that part in 2021.

UNC quarterback Sam Howell is a sensational talent, projected by most pundits to be the No. 1 pick in the 2022 NFL draft. A starter since the first game of his true freshman season, Howell has averaged nearly 300 passing yards per game and nearly five touchdowns per interception in his two-year career.

But can he keep that up after losing Javonte Williams, Michael Carter, Dazz Newsome and Dyami Brown, who combined for 9,090 yards from scrimmage and 81 touchdowns over the past two seasons?

If he can, then this game could have all sorts of College Football Playoff implications.

For the Tar Heels, this looks like, by far, the biggest test of the regular season. They don't face Clemson, they get both Miami and Florida State at home and the rest of their nonconference schedule (home against Georgia State, Wake Forest and Wofford) is more than winnable. If this truly is one of the 10 best teams in the country, this road game against Notre Dame could be the only thing that keeps them from carrying an undefeated record into the ACC championship.

Conversely, this should be Notre Dame's final big test prior to Selection Sunday.

The Fighting Irish will face Cincinnati, USC, Wisconsin, Florida State and Virginia Tech prior to playing North Carolina. Going unbeaten through that slate will be a challenge. But if they enter Halloween weekend with a playoff pulse and win this game, they should close out the regular season with victories over Navy, Virginia, Georgia Tech and Stanford to secure a spot in the national semifinals for the third time in four years.

As with the aforementioned USC-Notre Dame game, this one may hinge on how well Notre Dame's secondary can stifle one of the best quarterbacks in the country. But even if Howell has a big day, the Fighting Irish could get the W against a UNC defense that wasn't anything special in 2020.

4. Cincinnati at Indiana (Sept. 18) & Cincinnati at Notre Dame (Oct. 2)

Yes, I'm cheating by lumping two games together, but this is a massive opportunity for the Group of Five (G5) to finally prove it deserves a chance to play for a national championship.

The G5 representative in the New Year's Six has fared well in the CFP era. Boise State beat Arizona at the end of the 2014 season. Houston defeated Florida State the following year. UCF beat Auburn on New Year's Day 2018. Even the four losses were entertaining and competitive.

But that bowl season success has been too little, too late. Even when the G5 team does win, the inevitable narrative is that the Power Five team wasn't as invested in the game as its G5 opponent.

But two regular-season road games against nonconference opponents that should appear in the preseason AP Top 25?

Now we're talking.

Houston had a similar opportunity in 2016. The Cougars opened the season at No. 15 in the AP poll with games scheduled against No. 3 Oklahoma (neutral site) and No. 19 Louisville (home). They won both of those marquee games but lost three AAC games. Had they gone undefeated instead of slipping up against Navy, SMU and Memphis, they most likely would have earned a spot in the College Football Playoff.

With quarterback Desmond Ridder atop Cincinnati's long list of key returning starters, perhaps the Bearcats can do what Houston could not and run the table.

If they do defeat both Indiana and Notre Dame, it would serve as proof that they're well-rounded enough to hang with anyone. The Hoosiers want to win via the pass and turnover-forcing, momentum-shifting defense. The Fighting Irish prefer to run opponents into the ground on offense while taking a bend-don't-break approach on defense. The Bearcats have an idle week in between, but what a brutal two-game stretch.

3. Iowa at Iowa State (Sept. 11)

In most seasons, Iowa vs. Iowa State—aka the Cy-Hawk Series—doesn't mean much to anyone outside the Hawkeye State.

Iowa State has never claimed a share of a national championship, and Iowa's last one came in 1960. Not one of the previous 64 meetings was a ranked-against-ranked affair, and only one game has seen either team ranked seventh or better. (No. 3 Iowa annihilated Iowa State 57-3 in 1985.) Even the rivalry's Wikipedia page is only eight paragraphs long, in contrast to the novel written about the Iron Bowl.

But this year should provide quite the exception to the rule.

Nearly everyone returns from easily one of the best teams—if not the definitive best team—in program history, and Iowa State is likely to open the 2021 season in the Nos. 6-8 range of the AP Top 25. Head coach Matt Campbell had been building toward something special for the past few seasons, and the blanket bonus year of eligibility might be what pushes the Cyclones over the top and into the College Football Playoff.

Iowa could be doggone good too, though.

After opening the 2020 campaign with back-to-back losses by razor-thin margins, the Hawkeyes went on a six-game winning streak. It was their eighth consecutive winning season and their third straight time appearing in the final AP poll.

Iowa doesn't bring back nearly as many starters as Iowa State, but the Hawkeyes aren't hitting the reset button either. Replacing defensive linemen Daviyon Nixon and Chauncey Golston would be a colossal challenge for most programs, but losing a star edge-rusher or two has become a rite of passage for Iowa in recent years. As long as they don't have gaping holes on the D-line, the Hawkeyes should be able to live up to the preseason Top 20 expectations.

That said, if you have any uncertainty along the defensive line, facing a standout running back like Breece Hall could be a disaster. Hall led the nation in total rushing yards last season and averaged 146.0 total yards from scrimmage per game—edging Alabama's Najee Harris for first place among guys who played at least nine games. He (and home-field advantage) should be the difference in an ISU victory.

2. Oregon at Ohio State (Sept. 11)

Early-season showdowns between potential national championship contenders are always fun, especially when we have no idea who will start at quarterback for either team.

Ohio State's quarterback battle was to be expected. Justin Fields' departure to the NFL left the Buckeyes without a player who has attempted a pass in a collegiate game. As far as we know, it's a three-horse race between Jack Miller, C.J. Stroud and Kyle McCord (all freshmen) with no clear hierarchy in advance of fall camp. At any rate, head coach Ryan Day hasn't given any indication of which way he's leaning.

Oregon's quarterback battle was decidedly less expected. Tyler Shough won the job last fall only to enter the transfer portal (landing at Texas Tech) in February. Former Boston College graduate transfer Anthony Brown is the favorite, but freshmen Jay Butterfield, Ty Thompson and Robby Ashford will vie for that job over the next three months.

Neither team has the luxury of time to figure it out as this Week 2 matchup in Columbus figures to be a colossal piece of the College Football Playoff puzzle.

Combining various still-too-early top-25 rankings from around the web, it looks as though Ohio State will check in at No. 4 or No. 5 in the preseason AP poll while Oregon will land in the Nos. 10-12 range.

More noteworthy than the numbers is the reality that each team is expected to win its respective conference. If that holds true, and if Alabama, Clemson and Oklahoma take care of their business, the loser of this mid-September game could be the odd one out of the four-team playoff.

That's a lot of early pressure on a pair of unproven quarterbacks. It should be entertaining to see who rises to the occasion.

1. Clemson vs. Georgia (in Charlotte, North Carolina) (Sept. 4)

We can argue on the order of Nos. 2-8 or bicker about whether one of the honorable mentions should be in the top five. But this season opener between Clemson and Georgia is a no-brainer for the top spot.

Remove the "nonconference" qualifier, and aside from a couple of conference championships and the College Football Playoff, this would still be the obvious pick for No. 1.

Both teams will open the 2021 season ranked in the AP Top Five, and each has finished the past four seasons ranked No. 7 or better.

The loser could still reach the College Football Playoff, but a win will be a massive early feather in the cap for one of the nation's best teams.

There is also a ton of history between these programs. Clemson and Georgia have only met four times in the past quarter-century, most recently in 2014. Still, this will be the 65th head-to-head matchup between the schools separated by about 75 miles.

Better yet, this game marks the rekindling of an old rivalry. The Tigers and Bulldogs are also scheduled to square off in Week 1 of the 2024 season, as well as early in the 2029, 2030, 2032 and 2033 campaigns. Because of that, whether it is an instant classic or a blowout, we'll be talking about this game for years to come.

As far as who should win, that will depend on whether Clemson's reloaded offense or Georgia's retooled defense is in better shape.

Most of Clemson's offensive line (minus Jackson Carman) returns in 2021, but those warriors in the trenches will be surrounded by new faces. Meanwhile, Georgia lost seven defensive starters to either the NFL draft or the transfer portal, and it will be particularly green in the secondary.

Will Clemson quarterback D.J. Uiagalelei be able to capitalize on the Dawgs' inexperience, or will redshirt freshman Kelee Ringo and West Virginia transfer Tykee Smith reestablish UGA as one of the nation's best defenses?

I have no idea, but I've had the first Saturday of September circled on my calendar for months because I cannot wait to find out.