BY BILL COATS Saturday, December 4, 2010 12:25 am

David Vobora could complete the cycle Sunday. If he's in the starting lineup at weakside linebacker at Arizona, it'll mean that all six linebackers on the Rams' 53-man roster have started a game.

The oddity is that James Laurinaitis has started every game at middle linebacker and Na'il Diggs has started every game at strongside linebacker. The shuffling has taken place exclusively at weakside linebacker.

Vobora would be the fourth different starter there in the last five games. Larry Grant started the first seven contests. He was followed by Bryan Kehl for one game and Chris Chamberlain for two before Grant got another start last week at Denver.

"We've all kind of had our taste," said Vobora, a third-year pro out of Idaho. "I'm excited to face Arizona down there and just have the opportunity. I'm looking forward to it, and I want to make the most of it."

Coach Steve Spagnuolo explained that different defensive packages are more suited to one linebacker or another.

"We just want to have production out of all 11 guys over on defense," Spagnuolo said. "All those guys that have played in all those linebacker spots, except for James Laurinaitis, are all real key special-teams guys. So we've got to have them all available.

"Whether we go with a two-linebacker defense or a three-linebacker defense, those guys have got to go out there and play."

Vobora started 10 games last year at strongside linebacker. But with Diggs arriving via free agency, Vobora has been used in a reserve role this season.

"Spags had a talk with me early in training camp, just saying, 'Listen, we're going to need you in a variety of different roles. You need to be prepared for that,'" Vobora said. "So I've kind of just had that in the back of my mind and really kind of homed in on all three (positions) and being able to know different spots, different weeks, different scenarios.

"We've had guys banged-up to where I've had to know all three in a given week. I think it's helped my knowledge of our defense."

More Butler?

With Jerome Murphy nursing a hamstring injury, fellow cornerback Quincy Butler also might be brought out of drydock to help with the Rams' nickel packages. Butler has been among the team's inactives the last three games.

"It looks like it's my time to step up," Butler said. "I'm very excited. It's a good opportunity for me to get back on the field and show the guys that they can depend on me."

Butler, who started seven games for the Rams last season, was one of the final preseason cuts this year. He was re-signed Oct. 25. Rejoining the team that cut him wasn't a difficult decision, Butler stressed.

"It's a business. I know that things happen for a reason," he said. "Obviously, I'm back, so I can go out there and show them that I've gotten better. I've paid a little more attention to a lot of things we've been doing, learned how to study film better.

"Just anything to give me an edge to stay on the field and stay on the team."

Tight end depth

Another reserve who could get a shot vs. the Cardinals is tight end Derek Schouman. Since being acquired Nov. 16, Schouman has been trying to nail down the Rams' playbook.

"I feel like I'm coming along good and picking up the offense as we go," Schouman. "There's still a lot more I have to learn, but I think I have the basics."

Schouman explained that the Rams' approach bears little resemblance to the system he was in for three seasons with the Buffalo Bills. "Similar concepts here and there, but just starting over with a lot of different terms," he said.

Schouman might be needed as a third tight end, behind Billy Bajema and Daniel Fells, because rookie Michael Hoomanawanui is out for at least a month after spraining his ankle vs. the Broncos.

Ram-blings

Rams rookie quarterback Sam Bradford will receive the Missouri Athletic Club's "Sports Personality of the Year" award at a dinner Dec. 7 at the MAC downtown. Including Sunday's contest, the Cardinals have sold out all 51 games since University of Phoenix Stadium opened in 2006. Despite the chilly weather, the Rams practiced outside Friday after staying indoors Wednesday and Thursday. "I just thought the fresh air would be good for them," Spagnuolo said.