Tony Romo might be without two of his main blockers in the opener Sunday night at Washington.
Dallas Cowboys right tackle Marc Colombo and left guard Kyle Kosier missed practice again Wednesday because of knee injuries suffered during training camp, leaving little time for them to prove they are healthy enough to play this weekend.
Colombo is the surprise. He was supposed to have been back a week ago based on the initial timetable when he underwent arthroscopic surgery.
"If he doesn't practice this week, I would say he probably wouldn't play," coach Wade Phillips said.
Kosier sprained a ligament and is three weeks into a recovery that was expected to take 4 to 6 weeks.
Barron was acquired from St. Louis during the offseason to provide depth at both tackle spots. Holland was with Dallas last season, but was inactive for all 16 games. Both started in place of the starters during the preseason.
Phillips said going with a pair of backups wouldn't change the game plan much.
"I think the strength of the guys that are in there, Barron and Holland, are comparable to what we have so you don't have to change too much," he said. "Colombo pulled and did some things like that; well, Barron can do that. Montrae is a guard similar to what Kosier does. It's not a big change as far as the plays you run. And both can pass protect."
The Rams gave up on Barron because he never lived up to expectations as a first-round pick. He was slowed by injuries during training camp.
"The more work he gets, the more confidence we'll have in him," Phillips said.
Holland has drawn multiple penalties for false starts in the preseason.
The Cowboys could use as many healthy linemen as they can get after struggling to move the ball during the preseason. They've said bland play-calling was mostly to blame, calling their practices crisp and vowing to be ready to improve on last season, when they set a franchise record for yards but scored fewer points than the previous season, when they missed the playoffs.