J.J. Watt left Sunday night's game after going down with an injury at the end of the opening drive.

J.J. Watt left Sunday night's game between the Texans and Chiefs after getting injured at the end of the game's opening drive. The Texans announced that he has a tibial plateau fracture and NFL.com's Ian Rapoport reports that Watt is done for the season.

Watt was unable to put weight on his left leg as he walked to the sideline, and while he was on the ground after going down, he was being checked for a possible ACL or MCL injury, according to NBC's Michele Tafoya.

He was then taken to the locker room on a cart after being examined in a tent on the sideline. Tafoya reports that while on the cart, Watt had to hold his left leg over the side of the cart because other positions were too painful.

He was on crutches as he went to an ambulance to take him to the hospital from the stadium.

In addition to Watt, the Texans also lost linebacker Whitney Mercilus, who is done for the game with a chest injury.