Yu Darvish won't be rejoining the Chicago Cubs' rotation this weekend after sustaining a setback during a bullpen session on Thursday.
Manager Joe Maddon says the Japanese right-hander felt pain in his right arm.
Darvish will return to Chicago to be evaluated, and won't pitch Saturday as scheduled. He'll be replaced by Tyler Chatwood, who came off the paternity list.
Darvish said his strength and endurance was good after he played catch on Wednesday. He threw a five-inning, 57-pitch rehab start with Class A South Bend on Monday.
He's been on the disabled list since May 26 because of tendinitis in his right triceps, his second DL stint this season.
Darvish has a 4.95 ERA in eight starts with the Cubs since he signed a $126 million, six-year deal with the team in February.