Jan 1, 2012; Green Bay, WI, USA; Detroit Lions guard Stephen Peterman (66) during the game against the Green Bay Packers at Lambeau Field. The Packers defeated the Lions 45-41. Mandatory Credit: Jeff Hanisch-USA TODAY Sports

Today we take a look at how the Detroit Lions’ offensive guards performed during the 2012 season with a little help from the fine folks at Pro Football Focus.

The radar chart below shows the Pro Football Focus grades for the Lions’ guards that played at least 25% of team snaps and compares them to the best, worst and league average ratings. PFF grades each player on each play to produce a massively useful tool for evaluating the totality of a player’s season compared to others at his position.

[Editor's note: this post was prepared prior to the Lions' release of Stephen Peterman yesterday. Rather than re-work it, I'll let it run as originally written. Too bad this didn't hit the site yesterday morning, I would have looked a lot smarter.]

2012 Season Review
Rob Sims – Sims added some bulk in the offseason in hopes of adding some power and it looks to have paid off. His +2.8 run blocking rating from Pro Football Focus isn’t spectacular, but it is solidly positive for the first time since joining the Lions. His +13.8 overall rating is the best of his career and ranked 11th among all guards that played at least 25% of team snaps. Sims’ teammates voted him the offensive line MVP, a well deserved honor after a fine season.

Stephen Peterman – You want the good news or the bad news? The good news is that Stephen Peterman led all Lions’ starting offensive lineman with a +5.3 run block rating. The bad news is that he posted a team-worst -8.4 pass block rating. Peterman was ok in the screen game and rated well for penalties so overall he ends up with a pedestrian +0.8 overall rating – fitting considering the wild swing between run and pass. It all goes to prove what Lions fans already know: Stephen Peterman can be a maddening player to watch. One of the postmortem tidbits out of the Lions organization was that they allowed too much pressure up the middle. According to the PFF grades, the bullseye is squarely on Peterman’s back.

Offseason Plan
Rob Sims has emerged as a steady member of the Lions’ offensive line and he is under contract for the next two seasons. He has been pushing Pro Football Focus top ten guards list for the last two seasons but he carries a cap number of just $3.425 million while the ten highest cap hits for guards league wide range from $6 million to $10 million. The Lions are fine to stand pat at left guard.

Stephen Peterman may have posted the best run blocking grade of any Lions starting offensive lineman, but he can’t be labeled an asset in that regard. In fact, Peterman posted a -4.8 run block rating in 2011 while earning a +9.8 pass block rating. Go back to 2010 and he was a disaster in both areas. At this point we know what Stephen Peterman is. He is a below average guard that doesn’t have a particular strength.

With a 2013 cap number rivaling that of Rob Sims despite the same level of production, the Lions should look to free some cap space by replacing Stephen Peterman. Bill Nagy and Rodney Austin are in-house candidates while Riley Reiff may be another depending on what the Lions do at tackle. The draft remains another possibility. The point is that the Lions can do better than Peterman from a production/value standpoint and they have options at their disposal.

Previously: Wide Receivers, Offensive Tackles

*Those that have been around the Detroit Lions blogosphere for a while may recognize the approach presented as similar to Ty Schalter’s ‘Old Mother Hubbard’ series on The Lions in Winter. Don’t worry, he’s cool with what I’m doing here and has assured me that he’ll be back with Old Mother Hubbard later in the offseason.

Dec 9, 2012; Green Bay, WI, USA; Detroit Lions guard Rob Sims (67) during the game against the Green Bay Packers at Lambeau Field. Mandatory Credit: Benny Sieu-USA TODAY Sports

The Detroit Lions players recently voted on their year-end awards and Rob Sims has been voted the winner of the Erik Andolsek award, given annually to the team’s most outstanding offensive lineman.

Sims has been a steady player in his three years as a Lion. He has consistently earned positive grades according to Pro Football Focus over that time but that was mostly on the strength of his pass blocking. Sims made a point to add some bulk to improve his contributions to the Lions’ running game and it certainly showed in the results – at least on the individual level. Sims earned a +2.8 overall run blocking rating from Pro Football Focus, the first positive grade in that area since joining the Lions. Sims still graded out quite well in pass protection, earning a +10.1 from PFF. His +13.8 ranked 11th among all NFL guards in 2012.

The Lions offensive line may look different in 2013 but there won’t be any changes at left guard where Rob Sims has solidified his standing as one of the game’s best guards. Sims is signed through the 2014 season.

Dec. 2, 2012; Detroit, MI, USA; Indianapolis Colts quarterback Andrew Luck (12) is pressured by Detroit Lions defensive tackle Nick Fairley (98) in the first quarter at Ford Field. Mandatory Credit: Andrew Weber-USA TODAY Sports

EA Sports has released their weekly roster update for Madden 13 and Detroit Lions running back Joique Bell gets another ratings bump. His three point jump a week ago was among the biggest in that update and he’s up another two points this week.

Rob Sims was the only Lion to get a ratings drop of more than one point, falling from 89 to a still respectable 87.

Nick Fairley has received a couple ticks up in previous updates and gets another point this week to bring his overall rating to 86 overall. He also gets adjusted to number two on the defensive tackle depth chart with Corey Williams landing on IR.

Here is the full summary of changes to the Lions’ Madden roster this week:

See the full list of changes from around the league on the next page.