San Francisco Giants at Boston Red Sox: Final Score & Recap

The Boston Red Sox edged the San Francisco Giants 5-4 at Fenway Park on August 23, 2026, completing a tight win that the DiamondIQ model's estimate placed at a 68 percent home-team probability before first pitch and ultimately resolved to 100 percent in Boston's favor. The Giants struck first, plating two runs in the top of the first and adding another in the second, but Boston chipped away with single runs in the second and third before a decisive three-run fourth inning swung the game decisively in the Red Sox direction. San Francisco managed a run in the seventh but could not overcome the deficit, going scoreless the rest of the way against a Boston bullpen that held firm.

The fourth inning was the pivot point of the contest. Ceddanne Rafaela's single off Matt Wilkinson was the single highest-leverage offensive moment for Boston in that frame, adding 11.8 percentage points to the Red Sox win probability, followed closely by Connor Wong's double off the same pitcher at plus 11.5 percent. Wong had also been the subject of the biggest negative swing of the game, grounding out earlier in the second inning for a 10.3-point swing against Boston. In the seventh, Christian Koss nearly kept the Giants' hopes alive with a single off Jake Bennett worth 12.7 points in San Francisco's favor, but Drew Gilbert grounded into a double play in the eighth, a minus-11.6-point swing that effectively extinguished any remaining threat.

Rafaela finished as Boston's top offensive contributor by WPA at plus 15.2 percent with a RE24 of plus 1.6, with Nick Sogard adding plus 13.1 percent and Jahmai Jones contributing plus 10.1 percent. On the mound, Aroldis Chapman led all pitchers with a plus-15.2 percent WPA, followed by Tyron Guerrero at plus 10.8 percent and Sam Hentges at plus 8.7 percent, a trio that locked down the final innings and ensured Boston held onto the one-run margin.