McCutchen was batting with a runner on second in the first inning when he was struck in the left hand by a pitch from Ryan Dempster. He remained in the game to run the bases but was removed between innings and replaced by Jose Tabata.
The Pirates announced that McCutcheon does not have a fracture and is listed as day to day.
"It sounded bad at the plate," Pirates manager Clint Hurdle said. "A lot of discomfort where (the trainer) was working him. I don't think we could have gotten any better news than what we got. We'll just take it day to day."
The Cubs and Pirates were scoreless at the time of McCutchen's departure. McCutchen is enjoying his best big-league season, entering Friday's game hitting .271 with 20 home runs and 81 RBIs.
Tabata went 1 for 4 after replacing McCutchen and drove in the Pirates' final run of the day with a single in the 7th.