Deshaun Watson left Sunday's game after apparently suffering a serious leg injury.

The Cleveland Browns quarterback was carted off the field after his right calf muscle appeared to pop – which is usually a pretty good sign of an Achilles tendon injury.

Watson tucked the ball in to run, and with his first step the muscle buckled noticeably – the sight appeared very similar to Kevin Durant's Achilles tendon injury.

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The Browns' Deshaun Watson leaves the field after the Dallas Cowboys game in Cleveland on September 8, 2024. (AP Photo/Sue Ogrocki)

It's been a tough season for Watson and the Browns, who started 1-5. Last week they traded away Amari Cooper.

Watson is in his fourth year with the Browns after signing a fully guaranteed, $240 million contract that is on track to be arguably the worst deal in NFL history.

Watson was accused of sexual harassment by over two dozen women, forcing him to miss nearly two years of football.

Dorian Thompson-Robinson started the game for Cleveland, who face their AFC North rival, the Cincinnati Bengals. Jameis Winston was declared inactive before the game.

Watson was actually having perhaps his best game of the season until his injury – he had completed 15 of his 17 passes for 128 yards.

Browns quarterback Deshaun Watson makes his first run against the New York Giants at Huntington Bank Field on September 22, 2024 in Cleveland, Ohio. (Jeff Lange/USA Today Network via Imagn Images)

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The Browns didn't seem to miss him too much as they scored several plays later. Ironically, it was Nick Chubb who reached the end zone in his first game back since suffering a serious knee injury last year.

Browns quarterback Deshaun Watson reacts after failing to convert on third down against the Dallas Cowboys at Huntington Bank Field on September 8, 2024 in Cleveland. (IMAGN)

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The injury, assuming the worst, would end Watson's season. At the time of the injury, he had thrown for 1,020 yards with a completion percentage of 61.3, the second-worst mark of his career. He only has five touchdowns.

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