The Washington Nationals handed the St. Louis Cardinals a 6-2 defeat on February 21, 2026, at Roger Dean Chevrolet Stadium, erasing what had been a slim pre-game edge for St. Louis. The DiamondIQ model's estimate opened the day with a 54 percent home win probability for the Cardinals, but that figure collapsed to zero by the final out, as Washington seized control with a decisive fifth inning and never relinquished it.
The pivotal sequence came in the top of the fifth, where the Nationals did their most decisive damage against Ryan Fernandez. Maxwell Romero Jr. delivered the swing of the game, a home run that shifted win probability by plus-27.6 percent in Washington's favor and effectively put the outcome out of reach. Sergio Alcántara followed with a single that added another plus-10.7 percent, extending the rally. The Cardinals had shown some life in the bottom of the fourth when José Fermín doubled off Eddy Yean for a plus-12.0 percent swing, but Joshua Báez's strikeout in the same frame cost St. Louis 9.1 percent in win probability and blunted any real momentum. Harry Ford's single off Tyler Bradt in the top of the fourth, worth plus-7.9 percent, had already begun tilting the game Washington's way before the fifth-inning eruption made it definitive.
Romero Jr. finished as the game's top offensive performer by WPA at plus-24.4 percent with a RE24 of plus-2.3, while Harry Ford and Trey Lipscomb each contributed roughly plus-11 percent WPA and plus-0.8 RE24. On the mound, Isaac Lyon led Washington's pitching staff with a plus-8.3 percent WPA contribution, supported by Andry Lara at plus-5.2 percent and Erik Tolman at plus-3.6 percent. St. Louis managed just three hits and committed one error, never finding a consistent answer to a Nationals attack that produced seven hits and ran clean defensively through nine innings.
Analysis generated by DiamondIQ's model.