ASHBURN, Va. (AP) — A person with knowledge of the situation says the Washington Redskins plan to start Rex Grossman at quarterback over Donovan McNabb on Sunday against the Dallas Cowboys.

The person spoke to The Associated Press on condition of anonymity on Friday because coach Mike Shanahan had yet to announce the switch.

McNabb is struggling through his worst season since he was a rookie. He has a career-high 15 interceptions for the Redskins (5-8).

Grossman has appeared in one game this season, relieving McNabb in the final two minutes of a loss to Detroit.

The switch was first reported by CSNWashington.com.

Copyright 2010 The Associated Press.