Iglesias entered with runners on first and second after Wandy Peralta walked pinch-hitter Ben Zobrist and allowed a single to Ian Happ. Iglesias promptly walked Kris Bryant on four pitches and needed six pitches to retire Rizzo.

Iglesias was one strike away from finishing the eighth, but Rizzo fouled off a 96-mph fastball then evened the count on the fifth pitch, a ball. On the next pitch, Rizzo swung and missed at another 96-mph fastball.

Iglesias secured Cincinnati's first win by retiring Willson Contreras, Kyle Schwarber and Addison Russell in order in the ninth to finish off the combined two-hitter. Schwarber's strikeout in the ninth marked the 58th time a Cub has fanned through the first five games of the season -- an NL record.

It was his 13th save of more than one inning since the start of last season.

The right-hander's four-out save preserved a strong start by Tyler Mahle (1-0), who matched a career best by pitching six innings in his fifth career start and first outing against the Cubs.

The only hit Mahle allowed was a two-out triple to Javier Baez in the second inning.

Mahle fanned Contreras and Schwarber with two on in the first and struck out Chicago starter Tyler Chatwood after allowing Baez's triple to end the second. He also induced a double play on Addison Russell to end the fourth after walking Schwarber.

Eugenio Suarez scored the game's lone run when he tripled and came around on Adam Duvall's groundout in the fourth. The Reds stranded 10 and went 1-for-10 with runners in scoring position.

With the win, the Reds avoided their first 0-4 start since dropping the first six games of the 1995 season.

Chatwood (0-1) allowed one run on four hits and six walks in six innings during his debut for the Cubs, who lost for only the fifth time in their last 20 visits to Cincinnati.

--Field Level Media