T.J. Watt was knocked out of the Pittsburgh Steelers’ regular-season finale Saturday with a knee injury.  

The Steelers believe Watt suffered a MCL sprain but await further testing, ESPN's Adam Schefter reported.

Watt was having a whale of a game against the rival Baltimore Ravens with two sacks, extending his league-leading total to 19, and three tackles for loss. But in the third quarter Watt was forced to the locker room after an accidental collision with teammate Montravius Adams.

Watt’s leg appeared to buckle awkwardly as Adams ran into him on a pass play, and Watt was shown pounding the field in pain as trainers came out to examine him. He eventually walked to the blue medical tent with some assistance and was later shown walking slowly to the Pittsburgh locker room. The Steelers ruled him out around the start of the fourth quarter.

According to ESPN, Watt wanted to return to the game but the Steelers "wouldn't allow it."

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All eyes will be on Watt's health going forward, especially if the Steelers qualify for the playoffs. That's no guarantee, but Saturday's 17-10 win to sweep the top-seeded Ravens — who rested several key players, including likely MVP Lamar Jackson — was a big step in the right direction.

Steelers coach Mike Tomlin did not reveal the extent of Watt's knee injury after the game, but said he'd have more information in the days ahead.

"Obviously disappointed in that. But, you know, there are challenges in the game of football, there are challenges in life. So we'll deal with it, whatever it may be," Tomlin said.