Stephenson finished with 11 – one short of matching the team’s season-high, set by left-hander Amir Garrett on April 19 against Baltimore – as the Reds maintained their Pittsburgh dominance with a 9-5 win.
Right fielder Scott Schebler drove in three runs while falling a double short of the cycle. Schebler followed Adam Duvall’s 30th homer in the fifth with a two-run shot for his 25th and a 7-2 lead over Ivan Nova (11-10).
Schebler was hit by a pitch during his final shot at the cycle in the seventh.
Catcher Tucker Barnhart drove in two runs with a sacrifice fly in the second and a bases-loaded single in the fourth and as Cincinnati improved to 9-2 this season against Pittsburgh overall and 4-1 at Great American Ball Park.
The Pirates have lost four of their last five games and 10 of 13, including a six-game losing streak.
Eugenio Suarez scored three runs and extended his hitting streak to a career-high 10 games with a one-out double. He scored on Schebler’s first triple of the season.
Stephenson (2-4), who also won his last start on Saturday in Atlanta, lasted 5 2/3 innings, allowing seven hits and two runs with four walks. He left with the bases loaded in the sixth, but former starter Tim Adleman struck out pinch-hitter Jose Osuna.
Pittsburgh scored its first run against Stephenson when center fielder Billy Hamilton stumbled just as he was camping under Starling Marte’s two-out drive to deep left-center field, which went for an RBI double.
Schebler’s homer proved crucial when Josh Bell banged a three-run shot into the tunnel next to the Reds’ left-center field bullpen off of Adleman in the seventh. The Red got two of those runs back in the bottom of the inning as Daniel Hudson walked one batter and hit two more, setting up Patrick Kivlehan’s bases-loaded, two-run double.
Kivlehan leads the Reds with seven pinch-hits and is tied with Scooter Gennett for the team lead with five pinch-hit RBIs.