The Cubs said it was 96 degrees when Rosario exited during the bottom of the fifth inning Saturday. He hit a two-run homer in the top of the fifth, then left shortly after fielding a hit by Anthony Rizzo.
The Cubs said the heat index was 107. That's a calculation of how hot it feels, with humidity factored in.
There was a short break in the sixth after Twins catcher Wilson drew a walk. A couple of cups of water were brought out for him to sip and douse himself to cool off. Wilson wound up scoring and was replaced with the score tied at nine.
"I just couldn't catch my breath,'' he said. "My heart was fluttering. I felt dizzy. Started getting a headache. Just couldn't even hold a conversation in the dugout.''
Kepler also left early because of heat illness on an afternoon Cubs manager Joe Maddon described as the worst he has experienced during a major league game.
"That was a pretty brutal day,'' Maddon said. "If you put that on AstroTurf, that would have been like the worst ever.''
All three Twins players were treated with IVs.
Information from The Associated Press was used in this report.