With left guard
Mathis, 30, a former third-round pick, has played for four teams in his seven NFL seasons, including the Eagles (2011),
He is viewed as one of the top three guards on the market along with Grubbs and
Grubbs is rated higher than Mathis on most free-agent lists, but some prefer Mathis (here's one example). Given how Mathis bounced around the league before landing in Philadelphia and playing well last season, there should be concern about how he would translate if he left the Eagles for the Ravens. But at the very least, he would figure to be a solid replacement for Grubbs if that's how this situation plays out.