Turns out it's not as simple as just a straight-up competition between Scott Wells and Jason Spitz to start at center on the offensive line.

It's about finding the best center-right guard combination, with Wells, Spitz and second-year pro Josh Sitton in a three-man battle for two jobs.

During Saturday's first training camp practice on the new Ray Nitschke Field, the coaching staff rotated the three different center-right guard combinations throughout all the snaps with the No. 1 offensive line.

Most team drills started with Wells at center and Spitz at right guard, but then other first-team reps featured Spitz at center and Sitton at right guard, and also Wells at center with Sitton at right guard.

At this point there's no telling how it's going to shake out, but it appears all the combinations are in play. And even though Head Coach Mike McCarthy hasn't put a specific timetable on when decisions will be made, he indicated the staff would like to settle on a starting offensive line earlier than in past years, so the battle will be watched closely every day from the get-go.

"There is definitely competition going on in the interior of our line, and really all the way through," McCarthy said, also referring to the right tackle competition in the search to replace Mark Tauscher. "We're trying to find the best five and work all the different combinations that are needed."

Wells was the one who appeared to be on the outside looking in during the spring, but only because of circumstances. Wells had surgery in January to fix a shoulder problem that he said bothered him most of last season, and as a result he sat out all of the OTAs and mini-camp in June while the Spitz-Sitton combination took all the first-team snaps.

But now that he's medically cleared to play, Wells took the field Saturday ready to fight to keep his old job. He has started 42 games at center over the past three years, but if he's bitter about having his job thrown open to competition, he's not letting on and he's taking the professional approach.

"Anytime somebody doubts me, it serves as motivation for me, and this isn't my first time to have to face this increased attention," said Wells, a seventh-round draft pick in 2004 who began his pro career on the practice squad.

"We've got a lot of good players on this team, so naturally some competition comes off of that. And when you have an unsuccessful season, win-loss record, you kind of re-evaluate every position and you're looking to see what can make the team better."

Wells looked impressive in his first one-on-one pass blocking drills since late last season, perhaps a sign of how much he disliked sitting out of on-field workouts from before.

But the time off may have been the best thing for him after an injury-filled 2008 that also included a back/trunk injury early on. He said his shoulder surgery and rehab went well, and he's feeling in better shape at the start of training camp than he ever has. Not being able to practice throughout the spring kept him rehabbing and getting extra strength and conditioning work, which has contributed to his fitness level.

"The trainers and the strength and conditioning staff were real impressed with what he has done just the last couple of months," McCarthy said. "I look for Scott to come back at full strength."

Spitz and Sitton have been full strength all along, and they obviously hope to keep it that way.

Sitton appeared on his way to earning the starting right guard spot last summer as a rookie when he injured his knee in the third preseason game, forcing him to miss the first three regular-season contests. When he returned, he managed to play in 11 regular-season games with two starts.

While he's shown a lot of promise and potential for a young player as an aggressive run blocker, his limited playing time last year leaves some questions as to just what the Packers have in Sitton - questions he hopes to answer with a fully healthy camp.

Meanwhile, Spitz started all 16 games for the first time in his career last season, and he's the most versatile of the trio. He has started games at all three interior spots over his first three seasons, with 29 of his 41 starts coming at right guard (and six each at left guard and center).

"More than anything it's helped this ballclub out, the three years that I've played," Spitz said of his versatility. "If I continue to do that, and that's the hat I wear, then that's the hat I wear."

{sportsad300}But given the choice between being a utility reserve or a starter, Spitz would choose to start, and it doesn't matter to him whether it's center or right guard.

He knows he has to earn it, though. Just like Wells' 42 starts the last three years, Spitz's 41 career starts provide invaluable experience to draw upon, but they won't mean much in the final evaluation process.

"Every year guys want to start," Spitz said. "It's a fickle business and it's tough to keep these jobs. Guys coming in, year in year out, want to try to get them. It's just part of the business.

"The only thing I can worry about is coming in every day, just doing my job and playing my hardest. That's the only thing I can control right now."

And the only certainty in this line of work is uncertainty, with jobs on the line all the time.

"This isn't new," Wells said. "There's competition every year. You have to re-prove yourself year in, year out, and show that you deserve to be where you're at."