IRVING, Texas -- The Cowboys’ offensive line could look a lot different after next week’s bye.

Offensive coordinator Bill Callahan said he is hopeful that Monday night’s matchup with the Bears would be the last game that Phil Costa misses due to back problems that have bothered him since training camp. Once Costa has recovered, there could be an interesting conversation among the coaching staff about whether Costa or Ryan Cook should start at center.

There could also be a change made at right guard, a topic Callahan and head coach Jason Garrett danced around but didn’t deny Wednesday. The Cowboys have the option of replacing struggling Mackenzy Bernadeau with Derrick Dockery, a veteran with 113 career starts.

“The reason he’s here because we think he’s a good football player,” Garrett said when asked about the possibility of starting Dockery at right guard. “He’s played a lot of snaps in this league. He’s a veteran player. He’s healthier than he was last year for us. We feel like he is certainly a good option for us if something were to happen to the other guys.

“What we’ll do is evaluate those positions and every position on our football team and try to figure out who’s best starting for us and playing for us.”

Callahan said he has “too much respect for my guys” to publicly discuss potential lineup changes. But he acknowledged that the Cowboys need Bernadeau, who signed a four-year, $11 million deal to come to Dallas this offseason, to be better than he has been so far this season.

“We want more from him,” Callahan said. I’ve made this point to him. I’m not trying to send a message through the media to him, but we’ve sat down very point blank, very frank, and just told him, ‘Hey, we need to get you better. We’re going to keep working to get you better.’

“I’ve got to do a better job. I’ve got to do a better job with him, and we’re working together to try to make him the player he can be.”