September 14–15, at Philadelphia Phillies In this weekend inter-league series, Boston won the first game, 2–1. The winning run scored on a sacrifice fly by Andrew Benintendi in the top of the ninth inning. Boston also won the second game, 6–3. Christian Vázquez had a third-inning grand slam and a sixth inning solo homer. Red Sox won the series 2–0 (8–4 runs) September 17–19, vs. San Francisco Giants The opening game of this three-game inter-league series featured the Giants' Mike Yastrzemski, grandson of Hall of Fame inductee Carl Yastrzemski of the Red Sox; the younger Yastrzemski hit his 20th home run of the season in the fourth inning. San Francisco built a 5–1 lead through four innings, which became a 5–5 tie at the end of the sixth. With no further scoring in regulation, the game went into extra innings. The teams traded runs in the 13th inning, and the Giants pushed across a run in the 15th inning, for a 7–6 win. With a game duration of 5 hours and 54 minutes, the teams used a total of 24 pitchers, tying the major league record, and 50 players total. The second game of the series was an 11–3 win by the Giants, the 2,000th win of manager Bruce Bochy's career. Rafael Devers hit his 30th home run of the season, while Jackie Bradley Jr. hit his 20th. Before the game, a ceremonial first pitch was thrown by Carl Yastrzemski to his grandson Mike. The Red Sox won the final game of the series, 5–4, with Eduardo Rodríguez recording his 18th win of the season. All of Boston's run came in the first two innings. Xander Bogaerts was 2-for-4 with three RBIs, in his first MLB game as a designated hitter. Red Sox lost the series 1–2 (14–22 runs) September 20–23, at Tampa Bay Rays The opening game of this four-game series was won in 11 innings by the Rays, 5–4. With the Rays defending Mitch Moreland's at-bats with four outfielders, he hit two home runs and had all four RBIs for the Red Sox. A win by the Cleveland Indians while Boston's game was in progress eliminated the Red Sox from postseason contention. The second game of the series was again a 5–4 Rays win in 11 innings. Tied 3–3 after nine innings, Moreland homered for Boston to take a 4–3 lead in the top of the 11th. With