LSU receiver Ja'Marr ChaseMark Humphrey/Associated Press

For any number of reasons, dozens of college football players opted out of the 2020 season.

Whether for individual concerns, family considerations or something else, well-known stars, projected starters and backups alike are passing up the shortened season amid the coronavirus pandemic. And in many cases, the players have already declared for the 2021 NFL draft.

To be clear, all players mentioned in this piece have intentionally opted out. Anyone with an injury or suspension—or from a program not playing in the fall, such as the Big Ten or Pac-12—is not included in the opt-out group. Additionally, the objective is not to shame any of these carefully considered decisions.

Rather, the point is to provide an overview of the teams needing to replace several key players on the 2020 depth chart. Factors include number of players lost and projected role.

Miami DE Gregory RousseauBrynn Anderson/Associated Press

As of this writing, a half-dozen programs have one player who opted out. In each case, it was a major decision. Covering this topic without mentioning these players would feel incomplete.

Top ACC Players

Miami defensive end Gregory Rousseau, Virginia Tech cornerback Caleb Farley, Pitt defensive tackle Jaylen Twyman and Wake Forest receiver Sage Surratt all earned first-team All-ACC honors last season. They're all focusing on the 2021 NFL draft.

Rousseau and Surratt both appeared in the Top 15 of B/R draft expert Matt Miller's early 2021 big board. Miller also labeled Farley a likely first-round pick.

Georgia Loses Newman

Pete Thamel of Yahoo reported Jamie Newman has opted out. Georgia needs to replace three-year starter Jake Fromm, and Newman—a Wake Forest transfer—seemed the favorite. Instead, the Dawgs are expected to rely on USC transfer JT Daniels.

Pair of 1,000-Yard Rushers

Last season, Memphis redshirt freshman Kenneth Gainwell ranked fourth in the nation with 2,069 yards from scrimmage. Gainwell opted out and is headed for the draft as well. Oklahoma back Kennedy Brooks—who topped the 1,000-yard mark—may follow suit after opting out, though his plans are unclear.

Darriel Mack Jr.John Raoux/Associated Press

In a word: extensive.

UCF lost two returning starters in defensive tackle Kalia Davis and cornerback Tay Gowan. Last season, Davis provided 27 tackles with eight for loss and three sacks, and Gowan totaled 31 stops, two interceptions and eight pass breakups.

The offense also must replace second-string quarterback Darriel Mack Jr., who started three games in 2018. Quadry Jones is now slated as the backup to sophomore Dillon Gabriel.

Defensive linemen Mason Cholewa and Kendrick Wilson, defensive backs Elijah Benoit and Devunte Dawson and offensive linemen Allan Adams, Lamarius Benson and Adrian Medley round out the list.

Gerald Herbert/Associated Press

The hits keep coming for LSU.

All-American wide receiver Ja'Marr Chase decided to skip his junior year, leaving a massive void in the receiving corps. He led the country with 1,780 yards and 20 touchdowns last season. Terrace Marshall Jr. and Racey McMath are LSU's only returning receivers with more than five career catches.

And on defense, the Tigers are down three projected starters. Defensive tackle Tyler Shelvin, defensive end Neil Farrell Jr. and nickelback Kary Vincent Jr.—who each amassed at least 39 tackles last season—have all elected not to play.

Between these departures and the task of replacing 14 NFL draft picks, LSU is facing a massive challenge in 2020.

D.J. Ford (left)Wilfredo Lee/Associated Press

North Carolina's defensive backfield is still plenty talented, but the Tar Heels won't have as much depth as expected.

D.J. Ford ranked fifth on the team with 54 tackles last season and would've competed for a starting job at safety. Bryce Watts sat out 2019 after transferring from Virginia Tech, where he tallied 24 tackles, six pass breakups and an interception in 2018. Watts likely would have factored into the cornerback rotation.

Sophomore safety Javon Terry primarily contributed on special teams, ending the year with four tackles. Even if he didn't play much defense again, special teams is still a valuable role.

Offensive lineman Triston Miller, a redshirt freshman, also opted out.

Eddie McDoomJon Barash/Associated Press

Until UCF's news on Tuesday, first-year USF head coach Jeff Scott had the longest lists of opt-outs.

If there's a bright side, it's that South Florida probably didn't have big expectations for many of these players in 2020. Running back Josh Berry, cornerback Eugene Bowman, tight end Thomas Nance, defensive tackle John Waller and wideout Jernard Phillips all seemed likely to hold a reserve role this season.

But a couple of Michigan transfers—wide receiver Eddie McDoom and linebacker Devin Gil—may have been starters.

McDoom managed 13 catches for 174 yards for USF last season. Gil only played six games at Michigan in 2019 but finished the 2018 season with 33 tackles.

Jaylond AdamsAssociated Press

UAB is the front-runner, but Southern Miss has a legitimate chance at reaching the Conference USA Championship Game out of the West.

That goal is much tougher now.

Though top receiver Quez Watkins declared for the 2020 NFL draft, the Golden Eagles returned quarterback Jack Abraham and receivers Tim Jones and Jaylond Adams. The offense still has intriguing upside, but it needs to replace Adams too after he opted out. He caught 48 passes for 483 yards and two touchdowns last season.

Plus, defensive end Jacques Turner racked up 46 tackles with 13 for loss and 5.5 sacks in 2019. He'll be sorely missed after opting out, as will linebacker Racheem Boothe, who made 49 tackles. They plan to transfer, along with running back Steven Anderson.

Marqez BimageEric Gay/Associated Press

Texas hoped for a breakout season from Marqez Bimage, but the explosive pass-rusher won't be on the field this fall.

Bimage is the most notable of three absences for the Longhorns. Yes, he only has 19 career tackles. Nevertheless, Bimage entered 2020 with fairly high expectations as a potential starter in a new defense that better suited his athleticism.

Running back Daniel Young collected 526 yards from scrimmage as a true freshman in 2017 but totaled only 61 touches the last two seasons. Young probably trailed Keaontay Ingram, Roschon Johnson and Bijan Robinson on the depth chart.

Willie Tyler, a redshirt sophomore, would at least have competed for a backup role on the offensive line.

Vanderbilt coach Derek MasonMark Humphrey/Associated Press

Even as top tackler Dimitri Moore reversed his decision and will play, Vanderbilt still has several big absences.

More specifically, the offensive line. Cole Clemens, Bryce Bailey and Jonathan Stewart—who all notched at least nine appearances in 2019—each opted out. Clemens' absence in particular stings a rebuilding offense because he's a two-year starter.

The Commodores also lost kicker Oren Milstein, a graduate transfer from Columbia and potential starter.