BOURBONNAIS – Bears offensive lineman Chris Williams did not hesitate Saturday when coaches told him to replace J’Marcus Webb for a set of plays at starting left tackle.

“I just do what I’m told,” Williams said.

Perhaps more telling is that the position is up for grabs almost three weeks into camp.

The Bears appear to be in a bind when it comes to protecting Jay Cutler’s blind side. They returned to practice two days after a lopsided loss to the Denver Broncos, and a productive two-and-a-half hour session did little to quell questions about a renewed position battle.

Webb, who played into the second half Thursday long after his fellow starters had rested, opened practice with the first team before giving way to Williams. Both players shared repetitions for the remainder of practice, and Webb left without speaking to reporters.

Instead, Bears coach Lovie Smith was asked to explain the timeshare.

“Like every other decision we make, we had a chance to see guys in certain situations from the game,” Smith said, “and we’ll continue to look at different people.”

So is the starting position at left tackle open once again?

“All positions are open,” Smith said.

Not really.

Barring injuries, all but a few of the Bears’ starting jobs appear to be set heading into next weekend’s second preseason game against the Washington Redskins. Most position battles have to do with the last several spots on the roster, such as which player could survive final cuts as a sixth wide receiver or whether the team will keep nine or 10 defensive linemen.

At left tackle, the questions are far less trivial.

Neither Webb nor Williams has asserted himself to seize one of the team’s top starting jobs. In the absence of either one taking charge with muscle and a mean streak, the Bears could be forced to assign the job to whichever player makes fewer mistakes in critical situations.

Webb did little to help his cause in a 31-3 loss against the Broncos. He committed a false start in front of a home crowd, and he was part of a unit that allowed six sacks.

Bears center Roberto Garza spoke out in support of Webb, a 2010 seventh-round draft pick who started all 16 regular-season games at left tackle in 2011. But Garza took umbrage with a reporter’s suggestion that it was difficult to find motivation in early preseason games.

“Any time you’re on the field, you can’t [relax],” Garza said. “You’ve got to be ready to play. Those guys are competing for jobs. You’re competing for a job. Nobody’s job is really secure. You have to go out there and be ready to compete and execute the plays.”

If that task falls to Williams, he’ll accept. He has shuffled positions in camp as he has during his career, with 20 starts at left guard, 11 starts at right tackle and seven starts at left tackle.

Williams said the adjustment from tackle to guard and back again was not a big deal.

“It’s all O-line, man,” Williams said. “It’s hands and feet.”

As for who starts at left tackle, it’s a question. It quickly could develop into a problem.

“It’s still the first game of preseason,” Garza said. “It’s still early in camp. Unfortunately, you think you cleaned [old mistakes] up and you think you’re past that, but obviously we’re not. We’re going to continue to work and continue to execute and work on our techniques.”