The seven-inning game went to extras tied at one, and Tucker scored automatic runner Jarrod Dyson with a single off John Gant (0-2) in the eighth. Pittsburgh added two more runs with two outs on an RBI single by Bryan Reynolds and an error by third baseman Brad Miller of a ball hit by catcher Jacob Stalling.
''It was great you know,'' Stalling said. ''It feels like we haven't gotten any breaks lately. ''
Chad Kuhl delivered six innings of one-run ball for Pittsburgh, Chris Stratton (2-0) pitched a scoreless seventh and Richard Rodriguez allowed two runs but got his second save by pitching the eighth.
''I feel really good every time out there,'' said Kuhl, who missed last season with Tommy John surgery. ''I'm happy with where I'm at and excited to see where I go from here.''
St. Louis scored on a sacrifice fly by Kolten Wong and single by Paul Goldschmidt that bounced off Rodriguez. But Rodriguez struck out the final two batters, both left-handers, to nail down the win.
''When that happened, I thought, oh man is this for real right now,'' Stalling said about the infield single. ''Rich really bared down and threw his best fastballs of the day.''
It was the fifth extra-inning game this season for Pittsburgh and the first for St. Louis. This was the Pirates first victory in the new format, and dating to last season, they had lost 11 straight extra-inning games.
Yadier Molina led off the fifth with a home run against Kuhl for a 1-1 tie. It was Molina's 157th career home run, passing Matt Holiday for 11th on the Cardinals career list. He also passed Joe ''Ducky'' Medwick with his 924th career RBI for eighth in Cardinals history.
The Pirates took a 1-0 lead when Stallings hit a two-out single to score Tucker in the fourth inning for an unearned run off starter Kwang Hyun Kim, who pitched six innings. Stallings has hit safely in six of his last seven games.
''Today my overall command was not good,'' Kim said through a translator. ''I should not have allowed that run. I wasn't really efficient today.''
BACK AFTER SITTING OUT
OF Dexter Fowler returned to the starting lineup and played right field in Game 1 of the doubleheader. Fowler, along with pitcher Jack Flaherty, opted to sit out Wednesday's game to protest social injustice after the shooting of a Black man by a police officer in Wisconsin.
Flaherty said he discussed unified protest across baseball with players Thursday, but nothing materialized in part because of pushback from some players who didn't want to sit out.
''It's tough because yesterday would have been the day for league-wide action, and it wasn't able to happen league-wide yesterday,'' Flaherty said. ''Hopefully it could happen today, but it doesn't seem like it's going to be able to happen today.''
Pirates: OF Anthony Alford was claimed Thursday off waivers from the Toronto Blue Jays.
Cardinals: RHP Junior Fernandez was activated Thursday and added to the roster. ... St. Louis named RHP Seth Elledge as the 29th man for the roster of the doubleheader. ... the club also optioned Edmundo Sosa to the Springfield, Missouri, alternate-site camp.
Pirates: RHP Keone Kela (right forearm inflammation) was placed on the 10-day injured list. He has not pitched since leaving the Aug. 21 game against the Brewers. Pittsburgh's closer had been the subject of speculation ahead of the Aug. 31 trade deadline.
Cardinals: LHP Andrew Miller (shoulder fatigue) was placed on the 10-day injured list retroactive to Aug. 24. Miller (0-1, 4.76) has a team-leading two saves in two opportunities and seven total appearances this season.
Pirates: Rookie RHP Cody Ponce (0-1, 5.40) will start the second game. Ponce will be making his first major league start. In his last outing, he pitched three innings in relief against Minnesota on Aug. 6.
Cardinals: Rookie RHP Johan Oviedo (0-0, 3.60) will be making his second start this season in Game 2. On Aug. 19, he pitched five innings against the Cubs, allowing two hits and two runs.
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