IRVING, Texas — With the Dallas Cowboys trying to build off last weekend’s well-rounded victory over the Tennessee Titans, quarterback Tony Romo was held out of Wednesday’s practice due to back stiffness.

While Romo downplayed it, Wednesday is the first significant practice of the week as teams begin installing their game plans for the next opponent.

“I think the tightness just happens from based off volume of things you’ve done,” said Romo, who had surgery Dec. 27 to repair a herniated disk in his back. “Obviously, a lot of throwing we’ve done over the last few weeks. That part of it. And then just wanting to have the ability to always make sure that you feel good going into the rest of the week. I’ll be back. I’m good to go.”

Ordinarily, it would not be a big deal. But Romo, 34, is coming off back surgery last year. He also had back surgery before the 2013 season.

And while the Cowboys plan to lean on the run game to take pressure off Romo and move away from the team’s pass happy ways of the past, they don’t want to be typecast as a team limited on offense because of concerns about their quarterback’s ability to make all the throws.

“He is coming back from an injury,” Cowboys coach Jason Garrett said. “He is working his way back through, and there have been some good things over the first couple of weeks. He, like everybody else on our team, is trying to get better – learn from the things that weren’t good and try to build on the things that were.

“He’s trying to get himself physically right. He goes through a process to get himself right each and every day and over the course of a week. I think it’s an important thing for him try to continue to do. Hopefully, he will get better and better as the year goes on.”

It must be noted that Romo missed seven practices during training camp. He played only 48 snaps in two exhibition games as the Cowboys kept him in bubble wrap in hopes of him being ready the season opener.

Until Wednesday, he had participated in every practice since preparation for the regular-season opener began Sept. 1.

Romo insists he is fine and this is just another example of the Cowboys being cautious.

“Like we said throughout training camp, you have to be smart,” Romo said. “It’s just part of you understanding when your back gets tight, you’ve got to do those things, and you’ve got to go and do gluts, abs and hammer out functional strength stuff in the weight room and do a lot of things to enhance that. It’s been good.”

Romo has been sacked seven times through the first two games. Time will tell if he will continue to hold up.

THE SERIES: 32nd meeting. Dallas leads the series 16-15. Dallas has won the last two meetings and three of the last four. Dallas won last year 31-7. The Rams won the last meeting in St. Louis, 34-14, in 2008.

–WR Dez Bryant missed practice Wednesday because of a sore shoulder suffered last Sunday against the Titans. He is expected to practice Thursday and play against the Rams on Sunday.

–LB Rolando McClain missed practice Wednesday because of a groin injury. There is no guarantee he will practice Thursday, putting his status for Sunday’s game in limbo. The Cowboys are calling him day to day.

–DT Davon Coleman (calf) missed practice Tuesday and Wednesday after being injured in the weight room on Monday. He walking on crutches and is doubtful for the Rams game on Sunday.

–RB Joseph Randle (concussion) was held out of practice Wednesday and will not play against the Rams unless he passes a concussion test.

–DE Anthony Spencer was in pads Wednesday for the first time since he had microfracture surgery on his left knee last October. He went through some individual drills and was listed as limited on the official injury report. Spencer is not expected back in action for a couple of more weeks, but this was a positive step.

“It’s good to have Spence out there,” Garrett said. “He was in full pads and did some limited work early on in practice.”

–DE Lavar Edwards (knee) returned to practice Wednesday after missing Sunday’s game against the Titans. He should be available for the Rams game.

GAME PLAN: The Cowboys are moving to a run-based attack, which fits perfectly for Sunday’s game against a Rams defense that ranks 30th in the league against the run. They will stubbornly force the run with running back DeMarco Murray – especially with quarterback Tony Romo ailing with a stiff back. Defensively, the Cowboys will be focused on stopping the run against a Rams offense that is struggling to move the ball through the air.

KEY MATCHUPS:

Rams defensive end Robert Quinn vs. Cowboys left tackle Tyron Smith: Quinn is one of the league’s top rushers and the Rams’ best defensive player. If the Cowboys hope to get anything done in the passing game Smith must contain Quinn. Though Smith gave up a sack in the season opener he should be up to the task; he allowed on sack all of last season and none to Quinn in an early match up.

Cowboys running back DeMarco Murray vs. Rams rush defense: Murray has run wild against the Rams in the past, starting with his franchise-best 253 yards as a rookie in 2011. He also had 175 yards in a matchup last year, giving him 428 yards on 51 carries in two previous meetings. That the Rams are giving up 171 yards rushing per game so far this season could mean another big game for Murray.