McFarland (groin) began a rehab assignment with Single-A Stockton on Tuesday, allowing one run over one inning of work.
McFarland has been shelved for more than three weeks with a strained left groin but looks to be on the cusp of a return from the 15-day injured list. Because his absence has been brief, he may not require any additional minor-league appearances before coming off the IL. McFarland had not been scored upon in 12 of his last 13 appearances prior to getting shut down with the injury.