The veteran right-handed pitcher allowed just two hits and had eight strikeouts in eight innings to move to 5-5 on the season after the 2-1 triumph Sunday at Busch Stadium in St. Louis.
Neither team plated a run though four innings. Kolten Wong drew first blood for the Cardinals with a fifth inning sacrifice fly, scoring Jedd Gyorko. The Cardinals added their second tally with a Matt Carpenter RBI single in the eighth frame.
Cardinals manager Mike Shildt told reporters he looked Wainwright in the yees to determine if he had enough to complete the long outing.
"I don't do [that] very often, my job is to make the decision, and I've never been a talk-out-of-it guy," Shildt said. "But I did want to take his temperature, and he looked right at me and said, 'I got plenty of gas left.' I said, 'All right, keep the pedal down.'"
Wong was the only player in the game to record multiple hits, going 2-for-2 in the victory. The Cubs host the Los Angeles Angels at 4:05 p.m. Monday at Wrigley Field in Chicago.