Patriots' Sebastian Vollmer absent again

FOXBOROUGH, Mass. -- New England Patriots starting right tackle Sebastian Vollmer was not present for the team's practice Tuesday, marking the second straight day he's been absent.

It is unclear what is keeping Vollmer off the practice field. Vollmer played 22 of 91 snaps in Friday's preseason win against the Eagles, which was the same total as starting left guard Logan Mankins, as top starters played the first two series.

In Vollmer's absence, the Patriots would most likely insert four-year veteran Marcus Cannon into that spot. But with Cannon also working at left tackle at times in training camp, the club could always keep him there and play Nate Solder on the right side as well.

Elsewhere on the injury front, tight end D.J. Williams and defensive linemen Chris Jones and Sealver Siliga were absent Tuesday.

Meanwhile, tight end Michael Hoomanawanui, linebacker Cameron Gordon and offensive lineman Chris Martin worked on the lower field with members of the athletic training staff.