The two College Football Playoff favorites might each be without a starter in Saturday’s national semifinals and potentially in the national championship game.

Both Clemson and Alabama have suspended three players for their semifinals, the Cotton and Orange bowls, respectively.

Tigers defensive tackle Dexter Lawrence, plus reserve offensive lineman Zach Giella and reserve tight end Braden Galloway, tested positive for ostarine, a muscle-growth supplement prohibited by the World Anti-Doping Agency. Clemson Coach Dabo Swinney said the team was waiting on B-sample results, a test to weed out false positives, before ruling the players out. Those results should come in Wednesday or Thursday, he told reporters.

If the primary results are upheld, all three players could face a one-year suspension, though Lawrence will likely enter the NFL draft.

“This particular substance can come from anything,” Swinney said (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.

“ . . . We’re going to do everything we can to figure out if it is in the system. Heck, I don’t know. I mean, who’s to say that it is there? I mean, that’s what we’re being told, but there’s — they all will have legal representation, and there will be a process to go through to find out.”

Alabama Coach Nick Saban, meanwhile suspended starting offensive lineman Deonte Brown and two backups, Elliot Baker and Kendrick James, “due to a violation of team rules and policies.”

Saban did not comment on the manner of the violation, or which rules and policies were violated. It is unclear if the suspended players will rejoin the team if the Crimson Tide advances to the national championship game. Junior Lester Cotton, who began the year as a starter at left guard, will play in Brown’s place.

No. 2 Clemson plays No. 3 Notre Dame in the Cotton Bowl on Dec. 29, at 4 p.m. No. 1 Alabama faces No. 4 Oklahoma in the Orange Bowl later that day at 8 p.m.

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