Wada was on the mound with one out in the fourth when manager Rick Renteria, pitching coach Chris Bosio and a trainer came out to check on him.
A translator for the Japanese pitcher then joined the conversation, and Wada was replaced by Carlos Villanueva after a short talk on a warm and humid Friday afternoon at Wrigley Field.
Wada was charged with three runs, two earned, and three hits. He struck out two, walked one and hit two batters.
The Pirates had a 3-2 lead when the game was delayed by storms in the area with two outs in the top of the fifth.