CHICAGO – When the Bears chose Chris Williams with the 14th overall pick in the draft, they envisioned him making his NFL debut in Thursday night’s preseason opener against the Chiefs.

But that occasion will have to be put on hold after the first-round draft pick underwent surgery Wednesday night to repair a herniated disc in his lower back.

First-round pick Chris Williams is out indefinitely after having back surgery.

The rookie left tackle has been sidelined since sustaining a back strain July 24 in the second training camp practice. When the muscle issue subsided, Williams was further evaluated on Tuesday after new symptoms associated with a disc problem first appeared.

Williams was initially treated with anti-inflammatory medicine and his muscle spasms abated. Based on his progress, he started working out on an adjacent field during practice, but as the anti-inflammatory medicine wore off, his condition plateaued and eventually worsened.

The condition is an entirely new issue that is unrelated to any previous back injury.

“It is disappointing,” said coach Lovie Smith. “When you draft a player like that you have big plans for him and we still have big plans for him. It has just been delayed.

“We would like to have him out there, but injuries are a part of it. We are no different than any other team. The good part is that he is coming back.”

The Bears declined to give a timetable for Williams’ return, but indicated that they plan to keep the Vanderbilt product on the 53-man roster once the regular season begins.

“It’s a medical issue and they’re very confident he will be ready to go during the season,” said general manager Jerry Angelo. “We had it with Marcus Robinson and Charles Tillman. It’s a herniated disc. They’re a little bit different. The time frame might be a little bit different than their timetable, but he’s going to be healed and ready to go.”

Roster news: In addition to Williams, other Bears who weren’t active for Thursday night’s game included linebacker Hunter Hillenmeyer (hip), defensive tackle Dusty Dvoracek (calf), running back Kevin Jones (knee), guard Terrence Metcalf (knee) and linebacker Michael Okwo (leg).

Jamar Williams started in Hillenmeyer's place at strongside linebacker.

Among the Chiefs who did not play were both of Kansas City’s first-round draft picks, defensive tackle Glenn Dorsey (knee) and left tackle Branden Albert (foot).

Prior to Thursday night’s game, the Bears waived rookie running back Matt Lawrence.