Justin Blalock (ATL)
Regardless of whether New England finds a way to re-sign Logan Mankins, the interior offensive line will be one of the team’s primary concerns. Blalock played for a team that has two higher-priority free agents to re-sign on the offensive line (Clabo and Dahl), which could make him the most likely candidate to be playing for a different team next year. He is a solid starter and would likely come at a manageable price since he’s probably the fourth or fifth-best interior lineman on the market. If the Patriots decide to let Mankins walk, Blalock is a decent candidate to replace him.
Chris Chester (BAL)
It may seem unlikely to see a player from the Ravens joining the Pats when you consider all of the bad blood between the two teams in recent years, but the move would make sense for New England if the price is right. Chester has tremendous athleticism at the guard position, and he is in a similar position to Blalock since he plays for a team with much higher free agent priorities. He likely will be the third-best free agent lineman on his own team behind Yanda and Gaither. If the Ravens choose to keep both of those players in addition to signing an extension with DT Ngata, they might not want to throw more money in the trenches.
Ryan O’Callaghan (KC)
O’Callaghan played a few seasons for the Pats in a reserve role at tackle after being picked by the team in the 5th round of the 2006 draft. After being axed in the final round of cuts before the 2009 season, he caught on with Kansas City as a starter and seemed to play pretty fairly well. He missed a bunch of time due to injury in 2010 and left the door open to be replaced by Barry Richardson, so it is very possible he could hit the open market and come at a reasonable price tag. His familiarity with the coaches and the system would make him an interesting possibility for the Pats, though he would have to show continued improvement to warrant a starting spot. A more likely scenario would involve the team holding him for depth and taking a gamble that he could replace Light a year or two down the road.
Ryan Harris (DEN)
If the Patriots don’t re-sign Matt Light, they will need an experienced tackle to fill that void. Harris is an above-average run-blocker and is just 26 years old, and he’s had some valuable experience playing in a similar system to New England’s under Josh McDaniels. He will almost certainly be on his way out of Denver this year. He could see a lot of attention from a number of teams this offseason, so it’s possible that he could be out of New England’s price range. But if Light wants too much money, I wouldn’t be shocked to see New England use some of the money they were going to dedicate to Light to get Harris.
Eric Heitmann (SF)
It appears that the 49ers are working toward a long-term deal with C David Bass, who replaced Heitmann after the starting center was injured last year. While Heitmann is not a free agent yet, I can’t imagine the 49ers would pay him nearly $2 million this year to serve as a backup, and they don’t have a starting spot available for him at either guard position. He has several years of experience as a starter and could step in right away and contribute on New England’s offensive line, and his versatility could prove very useful in case of an injury.