ENGLEWOOD, Colo. (AP) - Peyton Manning is about to enter a season of Super Bowl expectations behind an offensive line that's full of questions, surgical scars, fresh faces and, yes, promise.
Three centers with a combined 18 career starts at the position are vying for the starting job now that J.D. Walton and Dan Koppen are out, and the leading candidate, Manny Ramirez, has none of those starts, although he was Denver's starting right guard for most of last season.
``Manny's played center since 2007. I was in Detroit when they drafted him,'' said Broncos offensive coordinator Adam Gase. ``He came to Detroit, he was a guard. You know what he was doing? He was working on center in practice. Now, I understand he hasn't done it in a game, but he was the starting guard on a 13-3 team last year, OK? He's been in some big situations, all right? And he's a very intelligent guy.''
Ryan Lilja and Steve Vallos have a little more experience in the middle but are also guards by trade and provide depth and flexibility more than anything.
Lilja played guard for six seasons with Manning in Indianapolis and then converted to center in Kansas City last year, then retired after the Chiefs went 2-14.
``It was just too good of an opportunity to pass up to come out here and play with these guys and try to wash this taste out of my mouth from a crummy season,'' Lilja said.
Manning's blindside protector, All-Pro left tackle Ryan Clady, is still working his way back from an offseason operation to repair a torn labrum in his right shoulder.
That means Chris Clark, who has never started an NFL game at tackle, will be the one charged with keeping outside linebacker Aldon Smith away from No. 18 in the Broncos' preseason opener Thursday night at San Francisco.
If the Broncos are worried about this patchwork pocket of protection for their $20 million man, it sure doesn't show.
Executive Vice President John Elway said his biggest takeaway from the first week of training camp was that Manning looks even better this summer than he did last season, which was, statistically, the second-best of his career, and that's had a ripple effect on the entire roster.
``I've seen a big difference in the way he's throwing the ball, the way the ball's coming off for him,'' Elway told Denver radio station 104.3 The Fan this week, ``and so that, for me, has made everything else look that much better.''
Manning said at the start of camp that he feels more comfortable in Year 2 in Denver, suggesting he recognizes how his surgically repaired neck will react to the rigors of football and also has a better feel for his receivers, save for Wes Welker, whom he's only been working with since March.
For all the consternation over who will be the one snapping Manning the ball this season, remember this: Ramirez has been the starter all offseason, even for the week's worth of practices that Koppen, last year's starter, attended before blowing out a knee and landing on I.R. last weekend.
Koppen was working primarily with backup QB Brock Osweiler and snapping to Manning only when Ramirez would slide over to get some work at guard.
Like Ramirez, Clark hasn't had a lot of experience at his current position. He has started a half-dozen NFL games, all at tight end during the Tim Tebow experiment in Denver a few years ago.
``Once again, he's got position flexibility,'' Gase said.
And that's the next best thing to stability.
Gase noted that the current five starters, including left guard Zane Beadles, right guard Louis Vasquez and right tackle Orlando Franklin, have been working together all offseason.
Beadles is the only Denver O-lineman who came out of last season unscathed. The rest needed offseason surgeries, including right guard Chris Kuper (ankle), whom the Broncos replaced in the starting lineup with Vasquez, who signed a $23.5 million, four-year deal when free agency was but 20 minutes old.
That gives Denver a 655-pound mountain of muscle on the right side to help a ground game led by rookie running back Montee Ball, the NCAA career touchdowns leader, and second-year speedster Ronnie Hillman.
``I think it's good how it's going with those two as far as getting used to playing with each other,'' Gase said. ``Obviously, with that group it's a game of chemistry and Clady's not in there, so Chris Clark's done a great job of trying to fill that role to the best of his ability. Obviously, Ryan's one of the top guys in the league. Would it be great if he was out there with Beadles right now? Absolutely. But Chris may be in that situation whether he's on the left or the right, if something happens to either one of those guys. So, they've got to get used to playing with him.''
Ramirez and Vasquez were teammates at Texas Tech, so that's helped them.
``We're like brothers. We have that comfort level,'' Ramirez said. ``I look at it as a blessing to be able to play at this level with your brother right next to you. So, we're looking forward to it.''
Notes: Defensive coordinator Jack Del Rio said SS Duke Ihenacho, an undrafted second-year pro from San Jose State, is his biggest surprise of camp so far. Ihenacho has worked in with the starters alongside FS Rahim Moore at times. ... DL Derek Wolfe was sent home sick so as not to infect other players.
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