Pittsburgh Pirates at St. Louis Cardinals: Final Score & Recap

The St. Louis Cardinals defeated the Pittsburgh Pirates 9-6 on May 19, 2026, at Busch Stadium, rallying from a five-run Pittsburgh outburst in the fifth inning to claim a walk-off victory in extras. The DiamondIQ model opened with a 63 percent home win probability before the game began, and by the final out that figure had reached 100 percent, reflecting a Cardinals team that steadily wrestled control back from a Pirates club that had briefly seized momentum.

The decisive turning points arrived in waves. Pittsburgh manufactured its biggest threat in the top of the fifth, when Bryan Reynolds delivered a double off Matthew Liberatore that swung win probability 21.3 percent in the Pirates' favor, keying a four-run frame that gave the visitors a temporary lead. St. Louis answered in the sixth when Nolan Gorman launched a home run off Evan Sisk, a swing worth 28.7 percent in win probability that began to shift the game back toward the Cardinals. Pittsburgh mounted one final charge in the top of the ninth, with Spencer Horwitz singling off Riley O'Brien to add 31.7 percent to Pittsburgh's win chances, only for Marcell Ozuna to ground into a double play moments later that erased 23.6 percent of those gains and stalled the rally decisively. In the bottom of the tenth, JJ Wetherholt ended it with a walk-off single off Mason Montgomery, a hit worth 29.5 percent in win probability.

Wetherholt finished as the game's top performer by the DiamondIQ model's estimate, posting a combined WPA of plus-37.7 percent and an RE24 of plus-1.8. Horwitz contributed plus-31.7 percent WPA despite the Pirates' ultimate defeat, while Gorman added plus-26.6 percent WPA and plus-1.7 RE24 on the strength of his sixth-inning homer. On the mound, JoJo Romero led Cardinals pitchers with plus-14.8 percent WPA, followed by Gordon Graceffo at plus-7.2 percent and Ryne Stanek at plus-4.5 percent in a bullpen effort that preserved the Cardinals' late advantage.