The 2015 recruiting class had its share of stars, including Kyler Murray, Saquon Barkley, Sam Darnold, Josh Rosen, Calvin Ridley and Christian Kirk.

But for every stud, there were plenty of flame-outs. In sports vernacular, they're called "busts," and this group had a number of them, especially near the top of the list.

For some, their college careers never took off. Others had OK tenures that sputtered and paled in comparison to the massive expectations. Another player on this list still has some of his story left to write, but he's got to play a lot better than he has so far to rewrite his college career.

A couple dealt with injuries, and their bust status isn't their fault.

From a pair of "can't-miss" defensive tackles that did to a duo of quarterbacks who couldn't cut it where they committed, the 2015 class is full of what-might've-beens.

This class had more busts than normal, so there is a big pool from which to choose.

Factoring in their 247Sports composite rankings, their production and their time remaining, let's take a look at the 10 biggest busts from the '15 class. All these players were ranked in the top 100 of the class.

10. Blake Barnett, Alabama, Quarterback

When 5-star quarterback Blake Barnett committed to the Alabama Crimson Tide, he was expected to be the next great signal-caller for Nick Saban who would keep the program surging in the post-AJ McCarron era.

Instead, he lost a battle with Jalen Hurts at the beginning of the 2016 season and bolted Tuscaloosa.

Unfortunately for Barnett, his career hasn't recovered. The native of Corona, California, resurfaced in Tempe to play for the Arizona State Sun Devils but couldn't beat out Manny Wilkins and attempted just five passes at that program before leaving for South Florida.

Barnett was a redshirt junior in 2018 and showed flashes at times for coach Charlie Strong's Bulls. He completed 61 percent of his passes for 2,705 yards, 12 touchdowns and 11 interceptions while rushing for 301 yards and eight more scores. Those are so-so stats for a team that crashed and burned halfway through the season.

South Florida desperately needs Barnett to regain the form that once made him a top-notch prospect. The best thing about the Cali native is his story is incomplete.

With one season of eligibility remaining, Barnett could erase his name from this list by leading an American Athletic Conference contender to big things in 2019. If he can do that, it'll be a huge conclusion to what has been an arduous odyssey.

Right now, he belongs on this list, but Barnett has the ability to turn things around. Unlike most of the players on this list, he's got a year of eligibility left.

9. Brian Cole, Michigan, Athlete

When Brian Cole came out of high school in Saginaw, Michigan, as the nation's No. 72 prospect and a versatile athlete who projected to play on either side of the ball, everybody expected big things.

Instead, after transferring from the Wolverines, he enters his final year at Mississippi State needing a big rebound to salvage any semblance of a successful college career.

He has potential, though.

Cole played three games as a wide receiver and special teams weapon for the Wolverines as a freshman, but he was released from the program in January 2016 for what sounded like maturity issues, according to comments he made to the Clarion Ledger's Will Sammon.

As a redshirt junior in 2018, Cole was a big part of coordinator Bob Shoop's defense in Starkville as a nickelback for five games before going down with a shoulder injury.

Cole had 11 tackles, including three for a loss, a sack and an interception in five games. He's still got another year to turn around his fortunes, which looked like they were recovering before the injury.

Shoop is an ideal coordinator to squeeze the most out of Cole's potential. But in Cole's absence last year, backup Jaquarius Landrews performed well, and the rising senior will have plenty of competition in the Bulldogs secondary in '19 as well.

Like Blake Barnett, Cole has the potential to shed the bust label, but he has to stay healthy and do some big things on the field. Still, it won't be for the team with which he signed.

8. Kahlil McKenzie, Tennessee, Defensive Tackle

Plenty of players among the nation's top 100 2015 prospects produced less than Tennessee's Kahlil McKenzie, but nobody ranked higher failed to do as much.

The 6'3", 339-pound defensive tackle came from an NFL pedigree that included his father, Reggie, and uncle Raleigh. He dominated camps and stepped right into the rotation with the Vols. Unfortunately for McKenzie and Tennessee, coach Butch Jones failed to develop him.

Welcome to the club. A long line of players at UT during Jones' era were lost in the same shuffle, such as Jonathan Kongbo, Todd Kelly Jr., Shy Tuttle and Kyle Phillips.

McKenzie, the No. 6 overall prospect, was supposed to have the same kind of "can't-miss" career as the nation's top-ranked talent, Georgia defensive tackle Trenton Thompson. The two were expected to battle to be the top defensive lineman in the SEC.

Instead, they battled for the title of most frustrating. Though Thompson had a couple of quality seasons in Athens, he left Georgia early and went undrafted.

McKenzie finished with 72 career tackles in 31 games with 5.5 tackles for a loss and three sacks in three seasons. When Jones was fired, McKenzie left a year early for the NFL.

Maybe he never should have played on the defensive side. The Kansas City Chiefs drafted him as an interior offensive lineman in the sixth round of the 2018 NFL draft, and though he didn't play as a rookie, he may have a future on offense.

He still never approached the dominant form he was anticipated to have in the SEC.

7. Byron Cowart, Auburn, Defensive End

Much like with Tennessee's Kahlil McKenzie and Georgia's Trenton Thompson, the recruiting battle for 5-star defensive end Byron Cowart was hotly contested. He was going to be a massive coup for the Auburn Tigers.

Unbelievably, as well as defensive coordinator Kevin Steele developed the defensive line on the Plains, the nation's No. 3 overall prospect in the '15 class wasn't included.

Cowart never fit in at Auburn after coming up from Seffner, Florida. He had just 15 tackles and 1.5 tackles for a loss with zero sacks in 26 games over three seasons. That's surprising considering how dominant he was on the high school level.

Cowart transferred to Maryland for his senior season in 2018. He cited a lack of playing time and his mother's health concerns as reasons for leaving AU, according to Pressbox.com's Luke Jackson.

He salvaged a bit of a career with the Terrapins, finishing the year with 38 tackles, three sacks, five tackles for a loss and two interceptions.

Cowart spoke about the adversity he experienced on Glenn Clark Radio, per Jackson:

"Coming out of high school, I was just thinking, 'OK, you see these highlights on YouTube.' Jadeveon Clowney was the guy at the time. I was No. 1 on ESPN. He was No. 1 [in 2011]. So I'm thinking, 'Boom, I'm going to have this Jadeveon Clowney career.' And I never once thought adversity. What happens if I don't fit this scheme for this team, or if I don't fit the defense? I didn't even know what adversity was."

Will Cowart get a chance in the NFL? It's possible, but his college career was a disappointment.

6. George Campbell, Florida State, Wide Receiver

Florida State has entered a tumultuous time in the first year-plus of the Willie Taggart era. Players failed to live up to expectations, transferred or got kicked off the team, and the ones left over failed to make a bowl game in 2018.

George Campbell, a talented wide receiver prospect in the class of 2015, is one of the players who is looking for a fresh start. He entered the transfer portal this offseason and is searching for a place to finish a college career derailed.

In Tallahassee, Campbell had just 13 catches in three seasons for 206 yards and no touchdowns.

Yes, that career spanned the same period where Deondre Francois was injured in '17 and freshman James Blackman played, as well as last year when Francois had no time to throw because of a porous offensive line.

Francois is off the team, and the 'Noles face concerning quarterback issues, so who can blame Campbell for looking elsewhere?

The 6'4", 202-pound receiver was a 5-star prospect in 247Sports' composite rankings and rated the 19th-best player in the nation. Big things were expected. None followed.

He's got one more year to turn things around, but his bust status, at least in Tallahassee, is solidified. Maybe a fresh start can change his fortunes.

5. DeChaun Holiday, UCLA, Outside Linebacker

It has been an interesting career for DeChaun Holiday, to say the least. When he committed to the UCLA Bruins, he was a 4-star cornerback from San Marcos, California, who was the 67th-best prospect in the country.

He grew into a 6'2", 220-pound outside linebacker. In three years, he played cornerback, safety and linebacker, and in 13 games he had just 13 tackles for the Bruins.

It was a huge deal when he pledged to coach Jim Mora's Bruins, but he never could find a positional home. Though it was announced in 2018 he was leaving the program after failing to find a spot under Chip Kelly, his name hasn't resurfaced anywhere else.

The former Army All-American Bowl participant looked like a potential star athlete who could play a lot of different positions. Unfortunately for him and the Bruins, that lack of a defined position became more of a negative than an asset.

Holiday wasn't fast enough to stick in the secondary, and he wasn't physical enough to get on the field under Mora or Kelly on the second level. If he's playing anywhere currently, there are no records of any statistics.

Every year, players like Holiday get recruited over or lost in the shuffle, but for a top-70 player to have such a small impact qualifies him for this list.

4. Torrance Gibson, Ohio State, Quarterback/Wide Receiver

Ohio State had a few swings-and-misses during the 2015 recruiting cycle.

While Justin Hilliard failed to live up to expectations, he was a key role player during his days in Columbus. That's more than Torrance Gibson can say.

The dual-threat quarterback/athlete from Florida was high on the list of many of the nation's top programs, but he camped in Columbus and earned an offer as a quarterback from the Buckeyes. Shortly after arriving on campus, though, he wound up at receiver, as most recruiting experts predicted.

Gibson never made an impact on the field.

The 6'4", 202-pound athlete left Ohio State and transferred to Mississippi Gulf Coast Community College in 2017, where he played quarterback, according to the NJCAA official site.

After playing in JUCO, he thought about trying for the NFL, but at last report, he was trying to latch on as a 6'5", 220-pound wide receiver for the Edmonton Eskimos of the Canadian Football League, according to the Edmonton Sun's Gerry Moddejonge.

"Everybody has a story to tell, so it's all good," Gibson told Moddejonge. "It is what it is. Everybody's going to have their side of the story. Until you ask me, everybody has their opinion. I just leave it in the past. I don't even bring it up. You've got to move on."

Gibson has no recorded stats with Edmonton, which is the same numbers he put up in FBS football: zeroes. It's hard to be labeled anything other than a bust when you don't play at all.

3. Canton Kaumatule, Oregon, Defensive End

At 6'7", 290 pounds, one of the most intriguing, exciting prospects with a high ceiling coming out of high school in 2015 was Oregon signee Canton Kaumatule.

He was a huge pull for the Ducks out of Honolulu as the nation's No. 17 overall player and a 5-star prospect. But in two seasons with Oregon, he barely sniffed the field, registering five total tackles.

In eight games as a freshman, he failed to make an impact. Injuries, specifically multiple concussions, took over in 2016, and he received a medical hardship waiver.

Kaumatule then announced a transfer to UCF but never played a game for the Knights. Though it's hard to label somebody who battled injuries a "bust," that's the nature of the word.

Kaumatule's brother Luke played at Stanford, and his younger brother, Falcon, has signed to play as an athlete for Utah. But Canton had the biggest upside, and it would have been fun to see a player with that size and ability off the edge blossom had he been healthy.

It stinks for Oregon, for the player and for college football that it didn't materialize.

2. Johnny Frasier, North Carolina State, Running Back

When 5'10", 229-pound power runner Johnny Frasier decided to stay in his home state and play for North Carolina State rather than head to Tallahassee to play for Jimbo Fisher at Florida State, it was believed to be one of the biggest recruiting coups of the cycle.

Unfortunately for the Wolfpack, Frasier's career hardly got off the ground.

The nation's No. 78-ranked player was expected to be a centerpiece for NCSU for years, but the product of Princeton, North Carolina, who was one of the highest-rated runners in the history of the state, redshirted in 2015.

He started the '16 campaign firmly in the rotation, but a shoulder injury forced him out of the lineup after just six games.

As Pack Pride's Michael Clark wrote last summer: "Due to academics and injuries, Frasier left the program in March 2017 and is not playing football at this time. You hate to label a kid a bust, but Frasier had a ton of natural ability and never lived up to his potential."

He finished his career with just 18 carries for 64 yards and a touchdown in Raleigh, and he is currently out of football. Frasier had a bunch of talent and potential, but he never could put it together.

What could have been a program-changing coup for the Wolfpack failed to materialize. Though coach Dave Doeren has done a commendable job keeping North Carolina State solidly on the second tier in the ACC, Frasier never was part of it.

1. Ricky Town, USC, Quarterback

Quarterbacks get most of the praise, most of the blame and many of the headlines. It's only appropriate a signal-caller takes the top spot on this list, especially considering how coveted Ricky Town was.

Though the prospect from Ventura, California, tumbled down the rankings a bit during his senior year, he was still rated No. 79 overall in the 2015 class. The 6'3", 206-pound quarterback originally committed to the Alabama Crimson Tide before decommitting from a group that already featured Blake Barnett.

After signing with USC, he became a poster boy for a class gone wrong for the Trojans.

That second-ranked class had some successes, but it also featured failed top-100 prospects like Town, Osa Masina (who dealt with serious legal issues off the field), Porter Gustin, Jacob Daniel and Ykili Ross. The two best players in that class, Sam Darnold and Cameron Smith, ranked outside the top 100.

Town couldn't crack the starting lineup with the Trojans, transferred to Arkansas but never played, and then finished his career at Pittsburgh. Town left the program in December after failing to beat out Kenny Pickett in 2018.

"I think he's got two more classes to graduate. He's a great kid. I appreciate everything he did for this football team," Pitt head coach Pat Narduzzi told reporters. "We needed Ricky when he came, and I appreciate his trust coming here."

Though players flame out all the time, it's staggering that a quarterback with the hype of Town attempted just one collegiate pass (a 15-yard completion as a junior for the Panthers). Surely a player of his ilk should've gotten a chance to play somewhere.

Town never did, and his college career was even less eventful than that of another star prospect who played for the Trojans and Razorbacks: Mitch Mustain.

Unless otherwise noted, stats courtesy of Sports Reference and CFBStats.com. All recruiting information is from 247Sports, and rankings are from the 247Sports composite.

Brad Shepard covers college football for Bleacher Report. You can follow him on Twitter @Brad_Shepard.