New England Patriots linebacker Derrick Burgess was not on-field for the start of training camp, and the 9-year veteran is contemplating retirement, ESPN.com's Len Pasquarelli reports.

Burgess appeared in 16 games for the Patriots in 2009, totaling 35 tackles, including 5 quarterback sacks. Burgess re-signed with the club on May 27, and was expected to earn $1.4 million in base salary, with his one-year deal worth a maximum of $1.65 million.

A third-round pick (63rd overall) out of Mississippi by the Philadelphia Eagles in 2001, Burgess has 262 tackles and 52 quarterback sacks during his nine-year career. Burgess missed all but one game in 2002 with a broken foot, and the entire 2003 season after rupturing his Achilles' tendon.

Burgess was in contention to start at one of the Patriots' outside linebacker positions.