ASHBURN, Va. — Washington Redskins rookie receiver Malcolm Kelly had arthroscopic surgery today on his left knee and is expected to be sidelined for two more weeks.

Kelly injured his right hamstring during training camp practice July 25 and has since been complaining of soreness in both knees. He returned last week to take part in some drills but was obviously laboring while on the field. He sat out Sunday's Hall of Fame game against the Indianapolis Colts.

The surgery, performed at the Andrews Institute in Pensacola, Fla., removed loose particles from the knee.

"It has been kind of stiff. ... We just thought we'd do things as soon as we can if there is a problem," coach Jim Zorn said.

Kelly was a second-round pick from Oklahoma in this year's draft. He and fellow rookie Devin Thomas were expected to contend for the No. 3 receiving spot, but both have been hurt for much of camp. Thomas missed Sunday's game with a hamstring injury and also isn't expect to play in Saturday's game against Buffalo.