Most costly player losses from 2015 college football rosters

What a luxury it was for Jimbo Fisher to have Aguayo for three seasons. During that time, he made every extra point and nearly 89 percent of his field goals. He went in the second round of the draft to the Bucs and will be difficult to replace.

Allen was drafted in the sixth round, giving way to his brother at Arkansas. A three-year starter, Allen had an excellent 9.3 yards per attempt and 30/8 TD/INT ratio in his senior season. The fall-off from the experienced Allen to brother Austin will probably be apparent, at least this season.

Booker struggled through some injury issues in his senior season, but he still had 1,261 rushing yards and 11 scores. He went to Denver in the fourth round of the draft, leaving a void for the Utes.

Bosa was a consensus All-American over the last two seasons, though his sack total did drop off from 13.5 in 2014 to five last year with more double teams. The attention that he drew for the Ohio State defense will be sorely missed.

Bowl game suspension aside, Boykin was the center of the TCU offense. He completed nearly 65 percent of his passes last season, throwing for 3,574 yards and rushing for 612 more. The Horned Frogs have a competition to replace him.

While the Spartans have viable options to replace Connor Cook at quarterback, replacing Burbridge's production could be more difficult. He emerged in his senior season to catch 85 balls for 1,258 yards and seven scores. He was drafted by the 49ers in the sixth round.

The Baylor Bears have no absence of weapons, but Coleman's contribution was exemplary. He had 74 catches for 1,363 yards and 20 touchdowns in his junior season before leaving for the NFL and was taken 15th overall by Cleveland. Baylor will have to use multiple players to replace him.

Arkansas also has serious turnover at running back between Collins and Jonathan Williams. Collins was the star, rushing for 1,577 yards and 20 touchdowns last season. He was drafted in the fifth round by Seattle and leaves a huge hole for the Razorbacks.

The Hilltoppers went 12-2 last season, with Doughty leading college football in passing yards. Fans hope he was more a product of the system than the cause of its success.

Ohio State has plenty of talent at running back behind Elliott, but he will surely be missed. The fourth overall pick in the draft by Dallas, Elliott rushed for more than 1,800 yards in consecutive seasons with 41 scores over that time.

When the Fighting Irish needed a home run, Fuller usually delivered. He averaged 20.3 yards per reception last season and had a total of 29 receiving touchdowns over the last two years. Fuller was drafted in the first round by Houston, while Notre Dame tries to find another deep threat.

The first overall pick in the draft, Goff helped Cal remain competitive in the brutal Pac-12. Last season he had 4,714 passing yards and 43 touchdowns, numbers that will nearly be impossible to match.

Grier was suspended after testing positive for PEDs in the middle of last season, and the Gators saw an immediate decline. Now he won't be returning at all, as Grier has opted to transfer to West Virginia. Florida has talent in its quarterback competition, but Grier would have likely been the guy if he was still in the program.

Hogan started four seasons for Stanford, and his career culminated completing nearly 68 percent of his passes in his senior season. His stats are replaceable in an offense led by running back Christian McCaffrey, but his leadership and smarts will be tough to replace this season.

Kelly was considered the leader of the Crimson Tide offense and a consensus All-American in his senior season. It's rare that a center would be impossible to replace, but that's certainly the case with Kelly, who went 18th overall in the draft to Indianapolis.

USC doesn't have a clear replacement for Kessler and plays a brutal schedule in 2016. Kessler made an elite contribution for the Trojans over the last three seasons and had a career passer rating of 156.4. He was drafted in the third round by Cleveland.

Lawson led college football in tackles for loss and also had 12.5 sacks in his junior season for Clemson. The defensive end went in the first round to Buffalo despite a shoulder injury.

Lynch almost singlehandedly helped the Tigers go from doormat to strong team during his career. They finished 9-4 last season, and Lynch threw for 3,778 yards and had 28/4 TD/INT. The Broncos took him in the first round as their hopeful long-term replacement for Peyton Manning.

Prescott did it all for the Bulldogs during his career, with a skill set reminiscent of a poor man's Cam Newton. He finished his career 11th all time in passing yards in the SEC and also had more than 2,500 rushing yards for his career. Dallas drafted him to back up Tony Romo, while Mississippi State has a competition to find a replacement.

Prosise started only one year for the Fighting Irish and had 6.6 yards per carry and 11 touchdowns. He went in the third round to Seattle, and Notre Dame can only hope to find someone with his efficiency this season.

Reynolds was everything to the Navy offense, running the option to perfection over four seasons. He had 4,001 career passing yards and 4,559 career rushing yards, with the Midshipmen peaking at 11-2 last season. They won no fewer than eight games per season in his four years, and he's now trying out at running back for the Ravens.

Smallwood rushed for 1,519 yards for the Mountaineers last season and could have a big role with the Eagles this season after going in the fifth round. West Virginia will find it difficult to replace is yardage per carry average.

Sudfeld was productive in a place that's hard to win, throwing for 3,573 yards and 27 touchdowns in his senior season at Indiana. The Hoosiers have a competition to replace Sudfeld, who was drafted by Washington in the sixth round.

The most explosive weapon on the Ole Miss offense over the last two years, Treadwell finished his junior season with 1,153 receiving yards and 11 scores. He was taken 23rd overall by the Vikings in the NFL Draft.

The Red Raiders are known for their passing offense, but they were two-dimensional over the last two seasons due in part to Washington. Last year he had 1,492 rushing yards and 14 scores on the ground. He went in the fifth round of the draft to Oakland.