JJ Watt suffered a tibial plateau fracture in his left leg during Sunday night's loss to the Kansas City Chiefs and will be out indefinitely, according to ESPN

The Houston Texans' defensive captain fell to the ground during the Chiefs' first drive of the game and needed to be helped off the field before being carted into the locker room. Watt was later seen leaving the X-ray room on crutches before he left the stadium in an ambulance.

Houston's head coach Bill O'Brien spoke about Watt's commitment to get back on the field after last night's game.

Per ESPN,

"I don't have a ton of information about it, but I feel terrible for the guy," Texans coach Bill O'Brien said of Watt. "But with that being said, just knowing him and knowing the type of guy that he is, he's an amazing human being. And he will work extremely hard to be back to play for this football team. I know that."

According to ESPN's Adam Schefter, Watt will undergo further testing on the leg and his recovery timetable is uncertain.

Watt, the three-time NFL Defensive Player of the Year, took to social media this morning to apologize to Texans fans and the city of Houston for not being able to finish the season. Last season, he missed 13 games due to a back injury.

In addition to Watt's season-ending injury, the Texans will also be without outside linebacker Whitney Mercilus for the remainder of the season after he suffered a torn pectoral on the same drive.

The Texans went on to lose last night's game 42-34, which puts them at 2-3 for the season. They'll remain in Houston for their Week 6 matchup against the winless Cleveland Browns.