Pittsburgh's Josh Bell tosses his batting helmet as he approaches home plate after hitting a walk-off, three-run home run in the bottom of the ninth.

PITTSBURGH — With the winning run on second base as he stepped into the batter’s box in the bottom of the ninth, Pittsburgh Pirates first baseman Josh Bell could feel his heart racing.

The rookie tried to get his breathing under control but couldn’t. Adrenaline won out. The Pirates, too.

Bell sent a 1-2 pitch from St. Louis Cardinals closer Seung Hwan into the seats in left field to give Pittsburgh a dramatic 5-2 victory Friday night. Bell’s 17th home run of the season was also his first walk-off hit in the majors, a show of power that gave the Pirates their sixth win in seven games as they try to climb into the thick of the underwhelming race in the NL Central.

“It was cool,” Bell said. “The lights go off and come back on, you’re rounding third and you see all your teammates at home. I haven’t had that feeling since Double-A, and the stadium here is a little louder than that.”

Adam Frazier led off the inning with a double and Oh intentionally walked Andrew McCutchen with one out. Bell missed badly at the first offering from Oh (1-5) and then took a ball and a called strike before putting the ball into the seats over the outstretched arm of Cardinals left fielder Tommy Pham.

“It was too high. It was a missed pitch,” Oh said.

Bell finished 2 for 3 with four RBIs. Frazier added three hits for Pittsburgh, and Gregory Polanco had two hits and an RBI.

Felipe Rivero (4-2) retired the Cardinals on seven pitches in the top of the ninth.

“That game was a bit of a roller coaster,” Bell said. “Setting the standard the first game of this series and the first game of this homestand was big.”

UP NEXT

Cardinals: RHP Lance Lynn (7-6, 3.61 ERA).

Pirates: RHP Jameson Taillon (5-2, 2.73) will make his third career start against the Cardinals on Saturday.