Boston Red Sox at Kansas City Royals: Final Score & Recap
Line Score
| Team | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | R | H | E |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| BOS | 3 | 0 | 3 | 2 | 0 | 1 | 0 | 0 | 0 | 9 | 13 | 0 |
| KC | 0 | 1 | 0 | 0 | 0 | 3 | 0 | 0 | 1 | 5 | 11 | 2 |
The Story
The Boston Red Sox handed the Kansas City Royals a 9-5 defeat at Kauffman Stadium on September 2, 2023, building an insurmountable lead through early-inning aggression that rendered the DiamondIQ model's pre-game 33 percent home win probability obsolete by the final out. Boston struck immediately, plating three runs in the first inning and adding three more in the third, while Kansas City managed just a single run through the first four frames. The Royals did claw back with three runs in the sixth, but Boston had already established too wide a margin, finishing with 13 hits and committing no errors compared to two from Kansas City.
The decisive swing in the game came in the top of the third, where Enmanuel Valdez delivered a single off Tucker Davidson that shifted win probability by plus 9.9 percent, the single largest play of the game. A Masataka Yoshida walk off Alec Marsh in that same inning added another plus 5.8 percent swing, compounding Boston's advantage during that critical frame. Kansas City's most significant counterpunch came in the bottom of the second, when Nelson Velázquez stroked a double off Tanner Houck to generate a plus 7.5 percent swing in the Royals' favor, and in the sixth MJ Melendez drew a walk off Josh Winckowski worth plus 7.3 percent. However, Salvador Perez's flyout in that same sixth inning cost Kansas City minus 5.8 percent in win probability, effectively snuffing out the rally before it could fully materialize.
Among individual performers, Melendez was Kansas City's standout contributor, finishing with a plus 12.1 percent WPA and a plus 3.0 RE24, the highest run-environment figures of any player on either side. For Boston, Valdez posted plus 9.3 percent WPA while Velázquez's plus 8.3 percent WPA led all Royals hitters despite the loss. On the mound, Houck paced Boston's pitching staff with a plus 3.5 percent WPA contribution, followed by Winckowski at plus 1.3 percent, as the DiamondIQ model's estimate of Kansas City's chances fell to zero percent by game's end.