Wood will make his Cubs debut against the Los Angeles Dodgers after going 1-3 with a 5.08 ERA at Triple-A Iowa this year. The left-hander was acquired from the Cincinnati Reds this offseason for reliever Sean Marshall.
Wood made his first major-league start at Wrigley Field in 2010 with the Reds. He's 1-0 with a 3.38 ERA in two career starts at the Friendly Confines.
Cubs manager Dale Sveum said Garza will most likely pitch the series opener in Milwaukee on Friday.
Chris Volstad took the loss on Saturday against the Dodgers, pitching in place of Garza.