CINCINNATI (AP) -- Right-hander Jackson Stephens lasted five innings in his major league debut and drove in the go-ahead runs with a bases-loaded single on Saturday, leading the Cincinnati Reds to a 5-3 victory over the struggling Chicago Cubs.
The Cubs' fourth loss in five games dropped them to 40-41, well off their pace from a year ago (51-30) when they were on their way to an NL Central title and a World Series championship.
Stephens (1-0) gave up a solo homer by Jon Jay and a two-run shot by Willson Contreras. He was called up to help the Reds fill an opening in the rotation created by Brandon Finnegan's arm injury.
With two outs and the bases loaded in the fourth, Stephens singled up the middle off Eddie Butler (4-3) for two runs and a 4-3 lead, smacking his hands together as he reached base with his first major league hit. He gave up six hits and struck out eight in five innings.
Raisel Iglesias escaped a two-on threat in the eighth and got the last four outs for his 15th save in 16 chances.
The Cubs got Kris Bryant back after the third baseman missed two games with a sprained right ankle. He singled in four at-bats.
Chicago managed only three singles while losing the series opener 5-0 on Friday night. The Cubs got to Stephens the second time through the order for a 3-0 lead. Jay led off the third inning with his first homer since May 24 of last season, and Contreras added a two-run shot.
Cincinnati sent nine batters to the plate in the fourth. Adam Duvall doubled home a run, and Butler walked Tucker Barnhart to force in a run with two outs and bring up Stephens, who singled on the first pitch.
Cubs: Ben Zobrist was activated off the DL and grounded out as a pinch hitter. He missed 17 games with an injured left wrist.
Reds: SS Zack Cozart got a day off. He returned from a thigh injury and single twice on Friday night. He'll get days off regularly as he's eased back into a starting role.
Cubs: Jake Arrieta (7-6) makes his first start since the Washington Nationals stole seven bases against him during the Cubs' 6-1 loss on Tuesday. Afterward, Miguel Montero blamed the pitcher's move to the plate, prompting the Cubs to let go of the catcher a day later.
Reds: Tim Adleman (5-4) is 3-2 with a 3.43 ERA in his last seven starts. He didn't get a decision in the Cubs' 6-5 win at Wrigley Field on April 21 after he allowed two runs in six innings.