DENVER -- The Houston Texans fear right tackle Derek Newton suffered torn patellar tendons in both knees before he was carted off in the first quarter of Monday night's 27-9 loss to the Denver Broncos, a source told ESPN's Adam Schefter.
Newton was taken to the airport in an ambulance but flew back to Houston with the Texans after the game.
Newton lay on the ground for an extended period while being checked out by the medical team and was seen pounding his right fist on the field. He had air casts put on both legs.
Tackle Chris Clark replaced Newton. Clark filled in at left tackle for Houston while Duane Brown was on the physically unable to perform list to start the season.
"I know how hard he's worked, how much he's put into this game," Brown said of Newton. "And then battling through injuries quite a bit. I know how that feels. I went through something similar to that last year, and my heart hurts for him and I'm praying for a speedy recovery for him."
Newton did not play in the Texans' Week 6 victory over the Indianapolis Colts because of an ankle injury. He also missed all of training camp with a hamstring injury, but he returned to play in the Texans' season opener against the Chicago Bears.
"It's tough to have anybody go down," Texans nose tackle Vince Wilfork said. "Just losing a starter, a key guy to our offense and to our team, it's a bummer. I haven't gotten a chance to see him."