ST. LOUIS (AP) Greg Robinson is no wide-eyed rookie anymore. The St. Louis Rams needed him to grow up fast.
The No. 2 pick of last year's draft qualifies as an experienced hand on the offensive line, given the team's massive makeover.
Robinson is the left tackle and two rookies are on track to start on the right side, second-round pick Rob Havenstein at tackle and third-rounder Jamon Brown at guard.
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Plus, former backups Barrett Jones, Tim Barnes and Demetrius Rhaney are competing at center.
The 22-year-old Robinson said he's answering any questions the rookies have, but didn't think he had that much to offer. Brown is also 22 and Havenstein is 23.
''It's just simple stuff,'' Robinson said. ''They're smart guys and I feel like they're a little bit more advanced than I was when I came in last year.''
The Rams heaped a lot on Robinson last summer, putting him out at right tackle at the start of camp. He got his first start at left tackle in November after Jake Long's season-ending knee injury after making his first NFL start at left guard in the Rams' fifth game.
Now, there's peace of mind. Just one spot to worry about.
''Last year I really dreaded playing guard,'' Robinson said. ''I had to make the most of it because it was my opportunity to play. I'm really appreciative of the position and I really want to hold it down.''
Like the other newcomers - Barnes has four starts and the rest none - Robinson is leaning on veteran left guard Rodger Saffold III. Saffold has 60 starts at three spots, most of them at left tackle.
Robinson said communication with Saffold has helped him get off the ball quicker.
''It's still not perfect, but I'm not expecting that,'' Robinson said. ''I really would say it's slowed down a lot and I'm able to use my eyes better and just use my feet altogether, so there's not much thinking.''
Getting everybody on the same page is the team's biggest concern.
''It's actually the lack of reps and the lack of experience,'' coach Jeff Fisher said. ''Because if there's a communication issue upfront and you cut somebody loose, that's a free run on your quarterback.
''So we've got to make sure that doesn't happen.''
Besides the 12 starts he got last season, Robinson arrived at camp much lighter on his feet. He played at 339 pounds as a rookie and weighed in at 313 Sunday before probably losing more in the steamiest practice conditions of the summer.
''You just look at what a year makes for these young guys,'' new offensive coordinator Frank Cignetti said. ''Greg is in great shape. He put in the time and effort in the offseason and summer time.
''You see it carry over on the field.''
At Auburn, Robinson said nutrition wasn't emphasized nearly as much. Bigger perhaps was better, too, in a run-oriented offense that sprung Tre Mason for 1,816 yards and a 5.7-yard average on the team that went to the national title game.
Robinson helped lead the way for both of Mason's 100-yard seasons last year.
''College, it was like a whirlwind - everything was moving so fast and I didn't really care what I ate,'' Robinson said. ''Now I'm able to slow and monitor what I eat.''
The team nutritionist also has helped him stay on track and avoid certain general hazards associated with being large.
''You know, when you're kind of big you get those back pains up in there,'' Robinson said. ''I want to stay away from those last year.''
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