ST. LOUIS -- Eugenio Suarez's grand slam may have been the final blow in a five-run fifth inning for the Reds that sent the Cardinals to a 6-0 loss on Wednesday night, but it was a play and pitch not executed that pushed the inning deep enough for things to unravel.
While Reds rookie starter Tyler Mahle skirted trouble en route to his first Major League victory, Cards rookie starter Jack Flaherty complicated his Busch Stadium debut with an inability to turn a double play and finish off Mahle after getting ahead in the count. The extra out and extra runner, along with a critical replay review and grand slam, produced a deluge of two-out runs that dropped the Cardinals into third place in the National League Central with 17 games to play in the regular season.
"We were very, very close to getting out of that inning and keeping it a one-run game, and then giving our offense a chance to get rolling," Cardinals manager Mike Matheny said.
Flaherty, who had wrapped up four efficient innings on 48 pitches, gave up an infield single to open the fifth before inducing a weak bouncer back to the mound. He gloved the ball and readied to start a potential double-play turn before losing his grip. He got only the one out.
Six pitches later, Flaherty's 2-2 changeup struck Mahle in the back.
"We're trying to go in, and it just got away from me a little bit," Flaherty said. "Obviously not what I was trying to do."
With the Reds poised to turn over the lineup for a third time, Matheny turned to another rookie in reliever Ryan Sherriff.
Sherriff retired Jesse Winker and got Zack Cozart to put a ground ball in play. Shortstop Paul DeJong made a diving stop and flip for a forceout attempt at second that, though initially called an inning-ending out, was overturned following a review. Mahle's hustle got him to the base just ahead of the throw.
"[First-base coach Freddie] Benavides was telling me if a base hit goes through then I needed to get to third, maybe draw that throw over there so we could score, so that's what I was thinking," Mahle said. "I was already running hard, so I was like, 'Oh I might beat this out.' I got lucky I was hustling."
Joey Votto foiled the Cardinals' preferred left-on-left matchup by slicing an RBI single to left, and Matheny stuck with Sherriff as the right-handed-hitting Suarez stepped in.
Suarez entered the night with better numbers against lefties (.274/.394/.504) than righties (.268/.373/.469). Sherriff, however, had held right-handed batters to a .218/.295/.290 slash line and one homer in 141 plate appearances with Triple-A Memphis. That success, along with the fact that another left-handed hitter loomed in the on-deck circle, factored into Matheny's decision.
"The sink that he has when he's been down in the zone, he's going to be able to get righties out just as easily as lefties," Matheny said. "He's been throwing the ball extremely well, and we're going to continue to throw him in those big situations because he can get righties as well as lefties."
Sherriff didn't get this one. After allowing one run in his first 7 2/3 Major League innings, Sherriff served up Suarez's second career grand slam. The blast put the Reds ahead by six, and the Cardinals, who had stranded seven over the first three innings, never advanced another runner into scoring position.
"[I was] just looking for something in my strike zone," Suarez said. "I just always want to put my best swing on it, and that was the perfect pitch he threw me right then and there, my hitting spot."
Jenifer Langosch has covered the Cardinals for MLB.com since 2012, and previously covered the Pirates from 2007-11. Follow her on Twitter and Facebook. This story was not subject to the approval of Major League Baseball or its clubs.