Texans OLB Jadeveon Clowney left his NFL debut after making one tackle Sunday. / Patric Schneider, AP
The injury problems continue for No. 1 draft pick Jadeveon Clowney.
Houston Texans head coach Bill O'Brien said the rookie outside linebacker had arthroscopic surgery on his right knee Monday morning to repair an injury suffered in Houston's season-opening win against the Washington Redskins.
Clowney left the game in the second quarter after landing awkwardly on the grass at NRG Field.
Clowney is expected to miss at least four to six weeks, O'Brien said in his Monday news conference.
O'Brien would not confirm the nature of Clowney's injury, but NFL Network reported Sunday night the Texans believed Clowney had suffered a torn meniscus.
"They went in there and tried to fix it," O'Brien said. "It went well."
The knee injury is just the latest blow in a rocky rookie year for Clowney, who was sidelined this summer while recovering from hernia surgery. He later missed more than week of practice and two preseason games while recovering from a concussion suffered during a practice in Englewood, Colo., against the Denver Broncos on Aug. 20.
"He's a great kid. A resilient kid. A good teammates since he walked in the door here," O'Brien said.
"He's disappointed, obviously. We've got great doctors here, and he'll be back. Will he be back tomorrow? No. But he'll be back soon."
Follow Lindsay H. Jones on Twitter @bylindsayhjones
Read the original story: Texans' Jadeveon Clowney out 4-6 weeks after knee surgery