Clemson defensive tackle Dexter Lawrence stretches before the Cotton Bowl. (Jim Cowsert/AP)

Three Clemson players, including starting defensive tackle Dexter Lawrence, will remain suspended for the College Football Playoff national championship game after supplemental samples of a failed drug test returned positive results for a banned muscle-growth supplement.

Lawrence, a junior, and reserves Zach Giella and Braden Galloway sat out the Cotton Bowl while those additional tests, used to weed out false positive results, were pending. The No. 2 Tigers trounced No. 3 Notre Dame, 30-3, and will play top-ranked Alabama on Jan. 7, for the national title.

Clemson Athletic Director Dan Radakovich said Thursday the NCAA upheld the players' suspensions, but will allow the players to travel with the rest of the team to Santa Clara, Calif., for the national championship game. Those bans could last up to a year, but Lawrence will likely enter the NFL draft. He is widely projected to be a first-round pick.

Lawrence told reporters Thursday he did not know how the banned substance, ostarine, entered his body and said he’d never taken performance-enhancing drugs.

“We get tested regularly and we know not to do anything stupid or selfish like that,” he said (via ESPN). “That’s why this is such a shock.”

“I didn’t want my last game to be Pitt [in the ACC championship],” he added. “I wanted my last game to be the closer. That’s what we’d been fighting for each game. I wouldn’t wish this on anybody.”

Tigers Coach Dabo Swinney said the team was investigating how ostarine came in contact with the three players. The substance is not approved by the FDA, but has reportedly been included in health supplements without being listed on the label. Swinney also said the team is also looking into other sources, including the team’s saltwater float pool.

“This particular substance can come from anything,” Swinney said last week when the initial test results came out (via ESPN). “And these three players have no clue — in fact, they thought it was a joke when I called them. They have no clue how this has gotten in their system.

“It could come from hair products. It could come from a cream. It could come from protein. It could come from a product that you order or buy online that you think there’s nothing wrong with it. It could be anything. Literally, it could be a drink — something in a drink.”

Alabama will also be missing three players for the title game, including starting offensive guard Deonte Brown and two backups, Elliot Baker and Kendrick James. Crimson Tide Coach Nick Saban suspended the three ahead of the Orange Bowl against No. 4 Oklahoma for what he initially described as “a violation of team rules and polices.”

Saban later said the suspensions were because of NCAA rules violations and that all three players were out for the national title game and “maybe beyond.”

“Those things [the NCAA violations] carry certain consequences,” Saban said (via AL.com). “And those players knew the situation. They made poor choices and decisions.”

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