Top free agent guards and centers

Here are PFF’s top interior offensive linemen set to hit free agency. While this year’s group of centers doesn’t stand out (albeit the addition of Alex Mack does strengthen the group), there are several difference-makers at guard that should be in high demand.

(Editor's note: This article was update at March 8, 2016.)

Guards

1. Kelechi Osemele

2015 team: Baltimore Ravens

Considering he’ll be 27 when the season starts, Osemele is the top guard set to hit free agency. He didn’t quite match his 2014 effort, but the former second-rounder still managed one of the better seasons among his peers, especially in run-blocking, where only four other guards finished with a higher grade. His pass protection hasn’t been quite as good, but is still above average—in 2015, he surrendered 13 total pressures in 417 pass-blocking snaps at left guard, the eighth-best rate of 82 qualifying guards. And few players provide the versatility of being able play on the outside at tackle, where he lined up during Baltimore’s last four games.

2. Evan Mathis

2015 team: Denver Broncos

Mathis bounced back after a rough start in Week 1, finishing the season right behind Incognito in our grades to go with a pair of outstanding playoff performances, including in the Super Bowl. There was almost no drop-off in his run-blocking last season, where he graded better than any other guard. Teams might be concerned that his pass protection took a bit of a hit; Mathis finished with a slightly below-average pass-blocking grade for the first time in seven seasons. But even if he won’t get back to his elite level of 2011-2013, Mathis (at age 34) still provides a good short-term option.

3. Brandon Brooks

2015 team: Houston Texans

Brooks is another zone-blocker with above-average marks in pass protection for all four years of his career—in fact, his grade has steadily improved there. His run-blocking was a bit below standard in 2015, but he ranked in the top five at the position there in both 2013 and 2014, so teams considering Brooks will likely hope he can return to that form in the run game. Brooks also has age (27) and durability—he was on the field for at least 93 percent of Houston’s offensive snaps over the last three seasons—on his side.

4. Ramon Foster

2015 team: Pittsburgh Steelers

2015 Grade: 82.3

Likewise, Foster has been a consistently above-average pass blocker over the last five seasons, and played in 100 percent of Pittsburgh’s offensive snaps in 2015, while ranking 20th in pass-blocking efficiency out of 82 qualifying guards. Foster should have no trouble finding a team after the Super Bowl, which highlighted the importance of good pass protection—whether he stays with the Steelers or goes elsewhere. It also helps that he’s coming off of a career-high grade in the run game.

Center

1. Alex Mack

2015 team: Cleveland Browns

A couple of years ago, it looked like Mack was on his way to Jacksonville, but the transition tag allowed Cleveland to match the contract offer and keep the former Pro Bowler. Unfortunately, Mack’s return was short-lived, as he suffered a broken leg in Week 6 of the following year. Now two seasons later, Mack has opted out of his contract to finally become a true free agent.

Prior to his injury in 2014, Mack was a very consistent player who continually graded among the top 10, if not top five, centers in the league. He did very well as a zone-run blocker at a position that is vital to the scheme’s success. He was also one of the most durable players. Mack missed over half a season due to a fluke injury, but otherwise, had not missed a snap in his seven seasons. In his first season back this year, though, he didn’t match that same level of performance we had seen from him in the years prior. Mack graded out average, with the 16th-best overall grade at center. Still, at 30 years old, he is young enough to potentially have several good years ahead of him—if he can get back to the level of play we are accustomed to seeing.

2. Stefen Wisniewski

2015 team: Jacksonville Jaguars

The top spot in a somewhat lackluster center group goes to Wisniewski, who’s coming off of a one-year deal in Jacksonville. Only three centers had a better pass-blocking efficiency than Wisniewski did last season, after allowing just 14 pressures in 686 snaps in pass protection, and he’s graded well above average there in four of five seasons. As a run blocker, he struggled at times in 2015—particularly during the Jaguars’ two-game stretch against Baltimore and Tennessee in Weeks 10 and 11—but for his career, he’s graded above average there. Teams should also be enticed by Wisniewski’s age (27 when the season starts) and durability, given that he’s played 5,174 out of 5,193 possible snaps over five seasons.

2. Manuel Ramirez

2015 team: Detroit Lions

Ramirez has split time between center and guard over his career, playing both spots in 2015. He looked back to his 2013 form in 502 snaps with the Lions, grading positively in both facets after a below-average final season in Denver. At age 33, Ramirez could offer a versatile short-term option—and he’s shown capability in both pass protection and run-blocking with positive grades in those areas for his career, though he’s been more solid than spectacular.

3. Ben Jones

2015 team: Houston Texans

Jones graded negatively overall in a contract year that included six penalties, the fourth-most among centers. Last season was also his first at center after spending his first three years at guard. At his best, Jones is a decent zone run-blocker who’s been slightly below average in pass protection, but has improved there each season.

4. Fernando Velasco

2015 team: Carolina Panthers

Another player who offers some experience at guard, Velasco has played limited snaps over the past two seasons in Carolina, including 116 in 2015. He graded positively in that playing time, looking competent on both run and passing plays, but any team considering him should look at 2012, Velasco’s best season by far. If he can regain that form, he could provide a decent medium-term option (age 31 when the season starts), but otherwise Velasco can at least provide average play in a reserve role based on last season.

5. Patrick Lewis

2015 team: Seattle Seahawks

Lewis has graded below average over the last two seasons in Seattle and struggled at the point of attack in the team’s two playoff games. He’s a young and likely cheap backup option who’s shown glimpses, with particularly solid performances in Weeks 11, 13, and 17.