The injury-plagued Wood is recovering from shoulder tendonitis. He threw 12 pitches -- 11 fastballs and a breaking ball -- during his fifth-inning appearance for the Class A Chiefs.
He was awarded the win in a 9-to-3 Chiefs victory over the Fort Wayne Wizards.
After the game, Wood said he felt great on the mound.
Wood was originally slated to start for Peoria. He said he decided he'd rather pitch out of the bullpen since that's how the Chicago Cubs are expected to use him.
Wood, who was named the 1998 National League Rookie of the Year, has been on the disabled list since the start of the regular season.