Jadeveon Clowney misses another practice, out for preseason opener

Houston Texans outside linebacker Jadeveon Clowney missed his fourth consecutive practice with knee soreness, coach Bill O'Brien said Friday.

Clowney did not travel with the team to Santa Clara for the joint practice with the San Francisco 49ers or Sunday's preseason opener. O'Brien said Clowney should return to the team next week and called the injury "not serious."

Clowney has dealt with injuries during his first two seasons in the NFL, playing in just 17 of 32 regular-season games. Last year, he missed time with a back injury and a Lisfranc sprain in his right foot.

Prior to his rookie season, Clowney had groin surgery and sustained a concussion during the preseason. He also seriously injured his knee in the first game of his rookie season and needed two surgeries to repair the lateral meniscus tear.

Rookie center Nick Martin also missed Friday's practice with "a little back issue" and did not travel with the team.