The Boston Red Sox defeated the San Diego Padres 5-2 at Fenway Park on April 3, 2026, in a game that began as a tightly contested pitchers' duel before Boston pulled away with a decisive sixth inning. The DiamondIQ model opened with the Red Sox as 54% favorites and closed at 100% certainty by game's end. San Diego managed only 4 hits and committed 1 error, while Boston collected 9 hits in a clean defensive performance.
The pivotal sequence came in the bottom of the sixth, when Marcelo Mayer delivered a home run off Wandy Peralta that swung win probability 20.7 points in Boston's favor, followed immediately by a Willson Contreras home run off Michael King that added another 14.7 points. Those two swings were the decisive turning point of the contest and account for the bulk of Boston's winning margin. San Diego had created its best opportunity in the top of the fifth, when Luis Campusano's double off Sonny Gray shifted win probability 13.7 points toward the Padres, and Miguel Andujar followed with a triple that added another 7.8 points, accounting for both San Diego runs. However, the Red Sox bullpen and defense kept the damage contained at two.
Mayer finished as the game's most impactful player by a significant margin, accumulating a combined WPA of plus 28.6% and a RE24 of plus 2.7. Contreras added plus 13.6% WPA while Campusano paced the Padres with plus 10.0% WPA despite being on the losing side. On the mound, Greg Weissert led Boston's relievers at plus 5.0% WPA, followed by Justin Slaten at plus 4.5%, while Sonny Gray contributed plus 4.0% WPA in a quality outing that kept San Diego's fifth-inning threat from fully materializing.
Analysis generated by DiamondIQ's model.