Williams traveled to Philadelphia to seek a second opinion from sports hernia specialist Dr. William Meyers when his hip didn't respond to an injection of pain medication, according to the Texans' official Web site. Williams' pain moved into his pelvic region and groin area and didn't respond to treatment The Houston Chronicle reported.
Kubiak didn't offer a specific diagnosis of Williams' injury. The 2006 No. 1 overall pick has dealt with the same injury before, the team's Web site reported, but he hasn't missed a game during his four-year NFL career. He's expected to continue the treatment prescribed by the Texans' doctors and trainers.
"I'm not going to sit here and tell you he'll be on the field tomorrow," Kubiak said. "We'll bring him back and see how he recovers from his visit there, see how he's doing, but we're expecting to see him on the field shortly."