Texans left tackle Duane Brown, who played every offensive snap against Kansas City in the season opener with a cast on his right hand, won't attempt those heroics again. In fact, it appears he won't play at all Sunday.

Brown's injured thumb, which he hurt in the preseason, hindered his effectiveness blocking, and the pain worsened significantly after he used the hand to brace himself on a hard fall after being accidentally undercut by teammate Alfred Blue

Not surprisingly, coach Bill O'Brien offered nothing definitive Thursday, saying only that Brown is in the "day-to-day category" and calling the decision "probably more of a medical question."

Chris Clark, Denver's starting left tackle in 2013 when the Broncos went to the Super Bowl, likely will step in for Brown. But Derek Newton might move over from the right tackle spot, with Clark, acquired in a preseason trade with the Broncos, taking his place. Or Jeff Adams could take over at right tackle, with Newton moving to left guard.

Adams, more of a tackle by trade, struggled at left guard against the Chiefs, contributing to Brown's problems.

The player who was supposed to have claimed the spot this season, 2014 second-round draft pick Xavier Su'a-filo, remains sidelined with an ankle injury.

Aboushi sees fastlearning curve

Oday Aboushi, the newest addition to the offensive line, likely won't be asked to contribute against Carolina on Sunday, but he'll get his chance sooner or later - probably sooner, considering the Texans' issues at left guard.

"Anybody that's signed onto the 53 (man roster) - and I'll say for the practice squad, too - I think all those guys have a shot to compete," Bill O'Brien said. "I made it clear to our football team this morning."

Aboushi, who was awarded to the Texans through waivers, started 10 games at left guard for the New York Jets last season when first-year Texans offensive line coach Mike Devlin held the same job under Rex Ryan

"Any time you've got a guy on your staff that's coached that guy and been a part of that guy's development, we always want to try to get that input," O'Brien said. "And Mike gave us good input. He has a lot of respect for Oday. Hopefully, Oday can come in here, add depth and battle hard to play for us."

Aboushi, a fifth-round draft pick by the Jets in 2013, said that's the plan while agreeing his ties to Devlin provide a huge plus for him.

"I came in here to compete, to win a starting job, and to help the team win. Just do whatever I can to put the team in the best position to win," he said. "Control what I can control, whatever reps I get at whatever position. Devlin drafted me, and I had two years with him.

"Coming in, being familiar with what he expects and the way he wants things done, has put me a little bit ahead of the learning curve."

Picking up the Texans' system, Aboushi added, is only complicated from the standpoint "of the details and terminology. I think it's just a matter of picking up the details and how they want things done and how they want plays run."

Coach says rosternot set in stone

Bill O'Brien suggested the Texans' 53-man roster remains fluid and that additional changes may be in the offing in the wake of the 27-20 loss to the Chiefs. Since Monday, the Texans have signed Oday Aboushi, traded receiver Keshawn Martin to the Patriots, and replaced Brian Hoyer with Ryan Mallett at quarterback.

"There will probably be some more moves. That's what this organization is about," O'Brien said. "It's a competitive league. It's a league about winning, and these aren't moves that are made in haste.

"These are moves that are made with a lot of thought."

Foster makingrapid recovery

Arian Foster returned to practice in a limited capacity, and while he definitely won't play Sunday, it was another indication his surgically repaired groin muscle is healing much faster than originally expected.

Rookie tight end Christian Covington (shoulder) was a full participant in practice along with rookie cornerback Kevin Johnson (bruised quadriceps).

Second-year safety Lonnie Ballentine underwent arthroscopic knee surgery this week and won't return any time soon - this after missing his rookie year with an injury. Also, inside linebacker Mike Mohamed (calf) is out for two to four weeks after getting hurt during practice last week.

Panthers middle linebacker Luke Kuechly, one of the top defensive players in the NFL, remains sidelined while he goes through the concussion testing protocol.

Dale Robertson