Under contract: Dominic Raiola (through 2013), Rob Sims (through 2014), Bill Nagy (through 2014), Rodney Austin (through 2014)

Free agents: Dylan Gandy (UFA)

The Detroit Lions went into the offseason looking to shake things up a bit at center and right guard. They are happy with starting left guard Rob Sims, but based on what happened last season, it seems like they have targeted center and right guard as areas where improvement is needed.

As part of their desire to get better at these positions, the Lions released Stephen Peterman, who had served as the starting right guard. Starting center Dominic Raiola had to take a pay cut to stay on the team, and it's clear that his time in Detroit is beginning to run out. He bought himself some time by restructuring his deal, but that doesn't mean he's guaranteed to be on the roster next season.

The two main in-house candidates to take over for Peterman are Bill Nagy and Rodney Austin. Both players have some experience at center, although Nagy is probably more likely to actually take a shot at the starting center job than Austin. The Lions got Nagy off waivers last year from the Dallas Cowboys (he started four games for them in 2011), and he spent all of 2012 on injured reserve. Austin was on the practice squad as a rookie last season, so there isn't much playing experience between them. Riley Reiff is another name to keep in mind, as he could potentially slide inside to guard if the Lions remain set at offensive tackle.