An otherwise unremarkable game between the Cleveland Browns and the Pittsburgh Steelers descended into chaos Thursday night when, with the game long decided, the Browns' Myles Garrett ripped the helmet off Steelers quarterback Mason Rudolph and hit him in the head with it.

"It's inexcusable," Browns quarterback Baker Mayfield — Garrett's own teammate — told Fox Sports after the game, which the Browns won, 21-7, in Cleveland. "I don't care, rivalry or not. We can't do that."

On Friday, the NFL suspended Garrett indefinitely for at least the rest of the season.

Garrett and two other players, Cleveland defensive tackle Larry Ogunjobi and Pittsburgh center Maurkice Pouncey, were ejected — Ogunjobi and Pouncey for their roles in the melee that ensued upon Garrett's attack, which came with just eight seconds left in the game.

During the brawl, Pouncey appeared to throw at least two punches and to kick Garrett in the helmet while he was on the ground.

.@MikePereira explains what kind of suspensions should be expected for players following tonight’s Steelers-Browns game. pic.twitter.com/2u8wwYvj4b — FOX Sports: NFL (@NFLonFOX) November 15, 2019

Earlier, Cleveland safety Damarious Randall had been ejected for a helmet-to-helmet hit on Pittsburgh wide receiver Diontae Johnson.

Rudolph said afterward that he was "fine — I'm good. Good to go." But he said, "I thought that was pretty cowardly, pretty bush league."

NFL.com, the National Football League's official website, reported that Garrett and the other participants in the fight would be under review for possibly lengthy suspensions. Garrett wasn't immediately made available for comment.

Garrett's actions were condemned not only by Mayfield but also by his coach, Freddie Kitchens.

"I'm embarrassed. Myles is embarrassed," Kitchens told reporters. "It's not good."

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Mayfield went further.

"That's just endangering the other team. He knows that. I hope he does now," Mayfield told Fox Sports.

"The reality is he's going to get suspended, and that's going to hurt our team."

Fox Sports analyst Troy Aikman called Garrett's actions "barbaric" during the broadcast, while Steelers coach Mike Tomlin pointedly refused to comment in his postgame news conference.

"I'll keep my thoughts to myself. You guys saw what happened at the end," Tomlin said. "No more questions about that, because I'm saying nothing."

To add to the drama, the two teams, which have a long and bitter rivalry, will play again in Pittsburgh on Dec. 1.