The much-anticipated NFL debut of Jadeveon Clowney was cut short in Sunday's 17-6 win at NRG Stadium.
The No. 1 overall pick was injured in the second quarter of the season opener against Washington. Clowney headed to the locker room shortly before halftime with a knee injury and did not return.
"I don't know what happened on the field," O'Brien said after the game. "I'm not sure what happened on that one. We're consulting with the doctors and trainers right now. I'm not sure about the status, but I will say right now that they think it's a good prognosis so it looks like it's going to be ok. He may miss some time, he may not. Who knows. We'll know better as the week goes on."
Clowney had one tackle on DeSean Jackson for a loss of nine yards following an attempted reverse. Third-year veteran Whitney Mercilus replaced Clowney at outside linebacker for the remainder of the game.