OXNARD, Calif. - Seemingly every practice, New Orleans Saints linebacker Jonathan Vilma has to pull a double-take on each side of him.

The names and numbers of the strongside and weakside linebackers playing with Vilma on the first-team defense has been a revolving door throughout the first four weeks of training camp.

Injuries and competition have spurred the constant shifting of players around Vilma as defensive coordinator Gregg Williams tries to find the right fit regardless of size and experience.

Jonathan Casillas and Scott Shanle are the two primary defenders vying for the starting weakside linebacker job. Shanle started the first preseason game, while Casillas started in Houston.

It’s more wide open on the strongside slot where Will Herring, Clint Ingram and third-round pick Martez Wilson are entrenched in a battle that may not be decided until the end of training camp.

“I think it has been very healthy and very competitive,” said Vilma, who’s starting position is the only one set in stone. “I think on both sides you have tremendous athletes that are playing well.

“That is all part of competition. That is probably a good thing right now. We have good athletes that can go out there and make plays. We are fortunate to have a good competition going.”

Herring and Ingram have both missed time this week with injuries, so Wilson has been seeing playing of time with the first-team defense. Payton said Wednesday that Wilson will get plenty of snaps in Sunday night’s preseason game in Oakland.

As far as the battle between Shanle and Casillas, Payton said he’s familiar with both players so it should make for an interesting next couple of weeks.

“We are getting a chance to see both of those guys,” Payton said. “We still have two more preseason games to go and a lot more before we make a decision.

“I see both of those players contributing, obviously. Both of those players are athletic. They both have experience. Certainly, Scott (Shanle) has more experience. Jon (Casillas) has done a great job. He is healthy now. Both of them are having solid camps.”

Slew of injuries

Nearly 20 percent of the Saints roster missed Wednesday’s third practice in Oxnard, Calif., as 17 players sat out with injuries.

Those missing the practice were RB Mark Ingram (knee), Carl Nicks (knee), RB Chris Ivory (foot/sports hernia), DE Greg Romeus (knee), LB Ezra Butler (hamstring/sports hernia), DT Tom Johnson (calf), CB Johnny Patrick (knee), DE Jeff Charleston (ankle), CB Fabian Washington (hamstring), LB Will Herring (calf), RB Chris Taylor (ankle), DT Aubrayo Franklin (knee), G Roger Allen (knee), LB Clint Ingram (hamstring), WR Jarred Fayson (knee), DE Junior Galette (knee) and DT Mitch King (unspecified).

The news was rather positive, though, for Mark Ingram as Payton said he should practice Thursday and play in Oakland.

Smith’s status uncertain

The status of defensive end Will Smith still remains up in the air as a St. Paul Pioneer Press report said his potential four-game suspension for using a banned substance may be reduced to two games and may not occur at the beginning of the regular season.

Payton said he read the report about a possible suspension reduction for Smith, but didn’t know anything more than what he read.