The Texans beat the Jets 23-17 to run their record to 5-0, but in the process may have lost inside linebacker Brian Cushing to a devastating knee injury.
The Houston Chronicle reports Cushing may have suffered a torn ACL in his left knee, which would end his season.
Cushing chose not to comment until he met with the team's doctors and had an MRI on Tuesday, but clearly his injury tempered the enthusiasm of the Texans maintaining their unbeaten record.
"We're very concerned, obviously, but I don't want to jump the gun," said Texans head coach Gary Kubiak after the game. "We're going to get home and get it looked at, but obviously very concerned.
"I don't really know what happened. They tell me upstairs he got cut on the play and his foot might have got stuck in the turf. Crisis No. 1.
"We'll just sit here and hope for the best."
Running back Arian Foster, who had a huge night, was among the first players to speak with Cushing after the injury.
"We don't know the extent of what it is yet," Foster said. "I just told him I got mad love for him.
"He plays the game with so much passion. He deserves to be known as one of the best linebackers in the game and to have an injury that puts him out of the game is tough."
Foster ran for 152 yards and one touchdown.
He becomes the third-fastest running back to go over 5000 career yards in NFL history.
"That's a collective effort from a lot of my teammates through the years and it's a good accomplishment," Foster said. "It's an individual accolade, but you play this game to win games."
Defensive end J.J. Watt had another huge game, with one quarterback sack and three deflected passes.
One of those deflections turned into an 86-yard interception return by Brice McCain that set up a Texans field goal right before the end of the first half.
"I wasn't getting a great pass rush on that play so I stuck my hand up, tipped the ball," Watt said. "It went right to Brice and he almost took it all the way. "That's a big play.
"They're about to score points and instead we get points right before the half."
The Texans continue as the only unbeaten team in the AFC and will play again on national television Sunday night against the Green Bay Packers.
"Very excited to get a victory on the road in a tough place to play against a good football team," said quarterback Matt Schaub. "To be 5-0 and this point we're extremely excited about it, but we can't be excited for too long. We've got a short week to get ready for Green Bay."