The St. Louis Cardinals stumbled against the Pirates for the second straight day, allowing home runs to Starling Marte and rookie Jordan Luplow in a stinging 4-1 loss to Pittsburgh on Sunday.
St. Louis began the day 1 1/2 games behind Colorado for the NL's second wild card.
With the score 1-1, Pat Bostick singled against Seung Hwan Oh (1-6) leading off the fifth and Marte followed with his seventh home run. Luplow went deep an inning later off Brett Cecil.
Jameson Taillon (8-7) allowed one run and four hits in five innings. Five pitchers combined for hitless relief, with Felipe Rivero striking out two in a perfect ninth for his 19th save in 21 chances.
Matt Carpenter hit his 22nd home run for St. Louis.
Pittsburgh has faded from contention but put together its first winning streak in three weeks by pouncing on the Cardinals' patched-together rotation. A day after chasing Lance Lynn in the first inning of an 11-6 victory, Pittsburgh pounced when the Cardinals went to the bullpen.
Still in the playoff mix thanks to a September surge, the Cardinals opted to give John Gant his first major league start. Gant worked three innings, allowing a sacrifice fly by Jose Osuna, while walking two and giving up three hits.
Taillon, finishing a season that included a month-long absence due to testicular cancer, battled through five innings in his final home start of the year. He needed 95 pitches to get 15 outs.
St. Louis loaded the bases with two outs in the seventh before George Kontos got Pham to hit into a forceout.
Luke Weaver (7-1, 2.05 ERA) starts Monday against the Chicago Cubs and LHP Jon Lester (11-8, 4.56) in the opener of a seven-game homestand.