Job responsibilities vary a little from guard to center, particularly when talking about pass protection, but things are pretty straightforward in the run game - put a hat on a hat, move people, and open up run lanes. Things are a bit trickier in pass protection; the center must stop a bull rush from a powerful nose tackle while simultaneously diagnosing any blitzes or stunts up the middle. Guards must be agile, as tackles will routinely pass off defensive ends to guards in an effort to pick up pass-rushing outside linebackers. Guards must also be capable of handling stunts and blitzes. We get on the line a lot, but blocking isn't easy, folks.
Don't read anything into the order in which Buffalo Bills players appear below - they appear based purely on level of NFL game experience, and nothing more.
63 - Geoff Hangartner. He didn't amaze in his first season as a Bill in 2009, but fans really underrate just how drastically better Buffalo's center play was with Hangartner in the pivot. That's not saying a lot, I realize, because Melvin Fowler and Duke Preston were that bad in 2008. Hangartner was a little dinged last season, but only missed a handful of snaps despite a lingering back issue. He's a tough, smart player that absolutely can hold his own against the AFC East's massive nose guards. He is not, however, the long-term solution at the position he currently plays.
67 - Andy Levitre. There's not a lineman on this roster that I'm higher on than Levitre, who enters his second NFL season as the one Bills lineman that played a full 16 games a year ago. Levitre flashed versatility as a rookie, flipping out to left tackle in a loss to Tennessee and acquitting himself well, and become Buffalo's best run blocker as the season wore on. He's not a physically imposing player, but he's very tough, very smart, very technically sound, and just keeps getting better and better. Levitre has just as much, if not more, long-term potential than fellow second-year pro Eric Wood, and has a chance to develop into one of the league's most underrated left guards in 2010.
70 - Eric Wood. Last year's coaching staff raved about Wood's work ethic and leadership potential, and like Levitre, Wood was really coming along nicely prior to the devastating lower leg injury he suffered in a Week 11 loss to Jacksonville. That injury is the biggest concern regarding Wood at the moment, as he may not be ready for the start of training camp late next month. Word is that the team expects him to be full-go by September 12, however, and once he gets back up to speed, he should emerge as an elite young player in his second pro season.
61 - Christian Gaddis. It's kind of amazing, really, how Gaddis has managed to find ways to stick with this organization for the past three years. He's spent time with Cleveland and Indianapolis, as well, skirting between practice squads and the back end of active rosters along the way. Right now, he's Buffalo's primary backup at the center position, but don't be surprised if the new coaching staff looks for a way to change that.
76 - Andre Ramsey. Saw a (very) little time at the revolving door that was Buffalo's left tackle position a year ago, committing a couple of very costly penalties and getting hurt along the way. Buffalo's previous coaching staff was pretty high on this guy, and he's got good size (6'5", 322) to play either tackle or guard at this level. He's got just as good a shot as any of Buffalo's young linemen of cracking the roster; all he'll need to do is play well.
66 - Jason Watkins. I'm high on Watkins purely from an athletic standpoint; in fact, I like him better than both Jamon Meredith and Ed Wang as a left tackle prospect. Watkins has been getting most of his reps at guard, however, so we'll include him in this analysis. I think he's got enough upside to merit a practice squad spot at a bare minimum, and he's got a chance to beat out Calloway for his roster spot, as well.
60 - Kyle Calloway. He played mostly right tackle at Iowa, and at 6'7" and 323 pounds, he's not your prototypical guard prospect. He'll spend his time swinging between right guard and right tackle to start, but the team likes his technique and mean streak. Limit your long-term expectations, because Calloway's lack of athleticism really puts a ceiling on his potential, but you can do far, far worse in terms of line depth than a blue-collar kid like this.
75 - Sean Allen. I like Allen's size (6'3", 305) and interior versatility. He gives the Bills a third center prospect behind Hangartner and Gaddis (Wood not counting, as he's still penciled in at right guard). A strong pre-season could land him a deep spot on the active roster, but he's far more likely to make the practice squad.
62 - Jorge Guerra. He played tackle in college, but will be shifting inside to guard at the NFL level. He's a tough player with some good skills, but his potential isn't considered significant. Has some value as a practice squad candidate.
Hangartner has three years and $7.7 million remaining on the free agent deal he signed in March of 2009. Levitre is also tied up for three more years, with $1.44 million in base salaries owed to him. Wood's got four years remaining on a five-year, $9.3 million deal he signed last July.
Calloway is likely to get a three- or four-year deal as a seventh-round pick. Allen and Guerra, as undrafted free agents, likely got multi-year deals as well. Gaddis will make $545K this year if he makes the team, and is scheduled for restricted free agency next spring. Contract details are unknown for both Ramsey and Watkins.
Along with right tackle (Cornell Green), Levitre's left guard spot and Hangartner's center spot are the only positions 100% set in stone entering the regular season, potential injury notwithstanding. Levitre really came on as the season progressed in 2009, and at this point in time, it's fair to say that he is Buffalo's best offensive lineman. Given Wood's ongoing recovery, Hangartner has virtually cemented his status as the starting center, though Wood still appears to be the preferred long-term option there. Wood's preparing for the start of the regular season, and I expect him to line up as the starting right guard on opening day against Miami.
Aside from the three obvious locks for the final roster, things get very tricky. I'm not as high on Calloway as most here are; he's very limited athletically, and while that's not a huge issue inside at guard, there's a transition he'll need to make, learning new techniques and leverages. He'll be fine in the long run, but I wouldn't expect much in the way of quality depth from him right out of the gate, particularly since he's still getting tackle reps. There are other players I'm intrigued by - Watkins and Allen in particular - but I think there's a chance that the Bills load up on O-Line depth at tackle. Guys like Kirk Chambers and Meredith can play guard in a pinch; in fact, Chambers has been getting first-team right guard reps in place of Wood this spring.
I'll predict that four players - Levitre, Hangartner, Wood and Calloway - make the final roster, along with five tackles (Bell, Green, Meredith, Chambers, Wang) to formulate the Bills' line depth. I'd be interested in the team retaining Watkins, who can swing out to tackle as well, and Allen, for depth at center, on the practice squad. But there's no reason to keep deep depth guys like that on the final roster.