Interior offensive linemen don't draw the offseason attention that players at more high-profile positions do, but they're important building blocks. This year's free agent class includes some promising young players, as well as veterans with a bunch of starts to their names.
Here's a glance at some of the top interior linemen in the 2013 free agent class:
Andy Levitre: Levitre contributed from day one for the Buffalo Bills, and in four seasons with the team, he started all 64 games. He made the NFL All-Rookie team in 2009, and he makes an attractive target because he's still just 26 years old.
Louis Vasquez: He is another good young player in the free agent class, and he has a lot of experience already. The 25 year old has made 54 starts over the course of his career, and he earned AFC West rookie of the year honors in 2009 while also being lauded for his pass protection skills. The Colts are rumored to be one of the teams interested in signing him.
Brandon Moore: The 10-year veteran has been a durable and reliable player throughout his career -- he hasn't missed a regular season start in any of the last eight seasons. He also earned a Pro Bowl trip in 2011.
Dan Koppen: Koppen has made 132 regular season starts in his career, and he also has plenty of postseason experience since he was a part of Patriots teams that won four AFC titles. He earned Pro Bowl and All-Pro honors in 2007. Following his release from New England, he signed with the Broncos, where he started 12 games in 2012.
Todd McClure: McClure has 14 years of experience under his belt, all of them with the Atlanta Falcons. He's appeared in 198 regular season games in that time, making 195 starts. It appears the Falcons may be ready to move on without him.
The full list of free agent interior linemen:
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