At a combined 624 pounds, rookies Breno Giacomini and Josh Sitton form a rather imposing right side of the offensive line during this weekend's rookie orientation camp inside the Don Hutson Center.

Whether or not that's a preview of a future Green Bay offensive line is impossible to know, but the 303-pound Giacomini at tackle and 319-pound Sitton at guard are taking nothing for granted during their first days as NFL players.

Knowing that in a couple of weeks they'll be thrown in with a group of linemen that includes five other draftees over the previous three years (Junius Coston in 2005, Jason Spitz, Daryn Colledge and Tony Moll in 2006, and Allen Barbre in 2007), Sitton and Giacomini are keeping their eyes and ears open this weekend for anything that can make them viable competitors for roster spots and/or playing time.

"They're changing up my footwork a little bit, my hand placement, everything, and that's what I'm ready for," said Giacomini, a fifth-round draft pick out of Louisville. "I'm ready for the coaching. I want to get better every day.

"Everything you can imagine, if you say it's a weakness or a strength, I want to improve on everything."

It's the right attitude to have. That same eagerness to learn has helped the quartet of 2005 and 2006 offensive line draftees start a combined 73 games over the past two seasons, led by Colledge with 28 and Spitz with 25. And Barbre, who played sparingly as a rookie last season, progressed in his first year to the point where he's expected to challenge for a starting job in Year 2.

Both Sitton and Giacomini are coming in with far more competition in front of them than the others did, as the Packers started from scratch at the guard position in 2006. But of the two, Sitton appears the most logical competitor for playing time as a rookie because he's getting an early look at guard, which is not a settled position heading into 2008, and he's also shown the versatility to play on either the right or left side.

"(During college) when I moved over and starting playing left guard and right guard and bouncing around, (scouts and coaches) noticed my versatility," said Sitton, drafted in the fourth round out of Central Florida. "I think that's really when I started turning a few heads.

"You have to be able to play more than one position at this level, and I definitely think versatility is my No. 1 attribute."

Meanwhile Giacomini is projected as a tackle, and most likely on the right side, though he'll likely get a look on the left side as well. He'll be trying to solidify almost strictly a backup role, and show enough promise to be considered a future replacement for veteran tackles Mark Tauscher or Chad Clifton.

"Right now on the field it's kind of slow, but once I get the playbook going and get the speed of the game, that's when my intensity will come back," he said. "Right now, it's a lot of learning. It takes steps to get intense, and I'll get there sooner or later."

Both Sitton and Giacomini know they have a lot to prove.

Despite being a full-time starter his final three years at Central Florida and blocking for a 2,500-yard rusher in Kevin Smith last year, Sitton wasn't even invited to the NFL Scouting Combine and had to rely on his Hula Bowl and pro day performances to have a place on teams' draft boards.

Giacomini, on the other hand, is a converted tight end (like Moll) who started only one full season on the offensive line at Louisville and has by no means fully honed his skills.

{sportsad300}No matter their breadth of experience, though, both realize the pro game will be a whole new experience.

"Everyone is just as strong as you, and most of the time they're better athletes than you at this level," Sitton said. "You can get away with certain things in college, because you might face two or three athletes who are just as good as these guys up here in a whole year in college. Up here you're facing that every time. It's a matter of doing it every play, every time, 100 percent, versus obviously the best talent."

That top-notch talent isn't necessarily lined up across from them this weekend in a rookie orientation, but it will be when OTAs start on May 19. That's why it's imperative to learn as much as they can this weekend, when they're just getting started.

"I can't wait to get back here," Giacomini said. "I know I have to leave tomorrow, but I want these two weeks to go by as fast as we can so I can come back and help the team win. That's what it's all about here."