My take then: "Watkins is a rookie fifth-round choice with college experience at both guard and both tackle spots. He's listed at 338 pounds and has weighed considerably more, but the scouting reports question his strength. Mattison started four games for the Rams last season after two seasons in Baltimore as a backup. I've wondered whether Quinn Ojinnaka might project as the starter here, but he's more apt to play tackle. Barry Richardson could be a consideration, as well."
The update: Ojinnaka has gotten the first-team snaps to this point. Watkins reported to camp out of shape. His chances should improve over time.
Richardson has been working with the first team at right tackle, ahead of Jason Smith. Richardson also played left tackle against Indianapolis in the preseason opener. Mattison practiced with the first team at left guard only when the Rams needed Ojinnaka to fill in for Rodger Saffold at left tackle.
Against the Colts, Mattison made a couple good blocks for Isaiah Pead in the second quarter. Ojinnaka appeared more comfortable in pass protection than as a run-blocker. The job appears to be Ojinnaka's to lose, but the team will want more of a mauler in the position long term. Developing Watkins has to be a priority even if Ojinnaka is better suited to start right away.
Kevin Hughes, an undrafted free agent in 2011, played left guard late in the game. He gave up a couple quarterback pressures under difficult circumstances as the Rams were well behind at that point.
This could be a position for the Rams to address in the 2013 draft.