(LOS ANGELES) -- Zack Greinke is ahead of schedule.
The Los Angeles Dodgers starting pitcher is set to begin a minor league rehab assignment in Class-A Rancho Cucamonga on Friday. He is recovering from a broken left collarbone suffered on April 11 when San Diego Padres outfielder Carlos Quentin charged the mound at Greinke after being hit by a pitch.
Greinke is about three weeks ahead of the original estimate that he would be out eight weeks after the injury. He has thrown two 60-pitch bullpen sessions and has been clocked at 90 mph.
"He really hasn't lost much time," Dodgers manager Don Mattingly said. "We feel like his arm strength is back."
Greinke made two starts before the injury, going 1-0 with a 1.59 ERA.
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