SAN FRANCISCO -- Cubs reliever John Grabow's season has ended.
Grabow felt something pop in his left knee during a rehab outing Monday in Mesa, Ariz., and an MRI on Tuesday revealed a Grade 3 sprain. He will have his knee immobilized for four to six weeks and be examined by the Cubs' orthopedic specialist to determine the next step.
Grabow has been on the disabled list since June 29. He appeared in 28 games and had a 7.36 ERA.