Before having a torn labrum in his left shoulder repaired a couple months ago, Jared Allen said he hadn't had surgery since getting his tonsils out at age 5.
It turns out the shoulder wasn't all the Minnesota Vikings' star pass rusher had fixed this time.
Allen underwent knee surgery on Jan. 31, the same day he had the shoulder repaired, two NFL sources said.
One source categorized the knee surgery as a "minor" cleanup job. The expectation is Allen should be ready for the team's June minicamp.
Allen played the entire season with the shoulder injury after learning before the season he'd need surgery eventually. He also was listed on the injury report with neck, groin and back issues, but any knee problems weren't revealed.
Set to turn 31 next week, Allen finished last season with 12 sacks, his sixth consecutive season in double figures. He didn't play as well as he did while amassing 22 sacks in 2011, though.
He now is coming off two surgeries as he enters the last season of a contract that includes a team-high base salary of $14,280,612 and cap number of $17,063,956.
The Vikings are not believed to have moved to restructure Allen's contract, though that still could happen before camp. Allen has played a ton of snaps in his nine-year NFL career, and concerns about wear and tear may give the team pause about extending his deal to free up cap space.
Prior to re-signing backup linebacker Marvin Mitchell on Tuesday, the Vikings were about $5.117 million under their adjusted cap for 2013.