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The MLB Belt · rivalry

Boston Red Sox vs. Seattle Mariners

48Belt meetings
25Red Sox wins
23Mariners wins
29Title changes

Boston Red Sox and Seattle Mariners have met 48 times with the MLB belt on the line, from July 25, 1985 to June 18, 2025. The belt changed hands in 29 of those games. Boston Red Sox lead the belt series 25–23.

Belt gameDateResult
16,061Jul 25, 1985Boston Red Sox beat Seattle Mariners 5–3Defense
16,062Jul 26, 1985Boston Red Sox beat Seattle Mariners 6–2Defense
16,063Jul 27, 1985Seattle Mariners beat Boston Red Sox 10–3Title change
16,064Jul 28, 1985Seattle Mariners beat Boston Red Sox 7–2Defense
16,315Apr 29, 1987Boston Red Sox beat Seattle Mariners 11–5Title change
16,316Apr 30, 1987Seattle Mariners beat Boston Red Sox 11–2Title change
16,828May 7, 1990Boston Red Sox beat Seattle Mariners 5–4Title change
16,829May 8, 1990Seattle Mariners beat Boston Red Sox 2–1Title change
16,830May 9, 1990Boston Red Sox beat Seattle Mariners 4–1Title change
17,488May 3, 1994Boston Red Sox beat Seattle Mariners 7–6Title change
17,489May 4, 1994Boston Red Sox beat Seattle Mariners 4–2Defense
17,678Aug 18, 1995Seattle Mariners beat Boston Red Sox 9–3Title change
17,679Aug 19, 1995Boston Red Sox beat Seattle Mariners 4–3Title change
17,680Aug 20, 1995Boston Red Sox beat Seattle Mariners 7–6Defense
17,688Aug 29, 1995Seattle Mariners beat Boston Red Sox 6–4Title change
17,689Aug 30, 1995Boston Red Sox beat Seattle Mariners 7–6Title change
17,690Aug 31, 1995Seattle Mariners beat Boston Red Sox 11–2Title change
17,889Apr 11, 1997Seattle Mariners beat Boston Red Sox 5–3Defense
17,890Apr 12, 1997Seattle Mariners beat Boston Red Sox 5–1Defense
17,891Apr 13, 1997Boston Red Sox beat Seattle Mariners 7–1Title change
18,158Aug 3, 1998Seattle Mariners beat Boston Red Sox 3–1Defense
18,159Aug 4, 1998Boston Red Sox beat Seattle Mariners 2–1Title change
18,323Aug 13, 1999Boston Red Sox beat Seattle Mariners 11–6Defense
18,324Aug 14, 1999Boston Red Sox beat Seattle Mariners 13–2Defense
18,325Aug 15, 1999Seattle Mariners beat Boston Red Sox 4–3Title change
19,394Apr 14, 2006Boston Red Sox beat Seattle Mariners 2–1Title change
19,395Apr 15, 2006Seattle Mariners beat Boston Red Sox 3–0Title change
19,396Apr 16, 2006Boston Red Sox beat Seattle Mariners 3–2Title change
19,397Apr 17, 2006Boston Red Sox beat Seattle Mariners 7–6Defense
19,479Jul 21, 2006Boston Red Sox beat Seattle Mariners 9–4Defense
19,480Jul 22, 2006Seattle Mariners beat Boston Red Sox 5–2Title change
19,481Jul 23, 2006Seattle Mariners beat Boston Red Sox 9–8Defense
20,230Apr 29, 2011Seattle Mariners beat Boston Red Sox 5–4Title change
20,231Apr 30, 2011Seattle Mariners beat Boston Red Sox 2–0Defense
20,232May 1, 2011Boston Red Sox beat Seattle Mariners 3–2Title change
21,015Aug 14, 2015Boston Red Sox beat Seattle Mariners 15–1Title change
21,016Aug 15, 2015Boston Red Sox beat Seattle Mariners 22–10Defense
21,017Aug 16, 2015Seattle Mariners beat Boston Red Sox 10–8Title change
21,567Mar 28, 2019Seattle Mariners beat Boston Red Sox 12–4Title change
21,568Mar 29, 2019Boston Red Sox beat Seattle Mariners 7–6Title change
21,569Mar 30, 2019Seattle Mariners beat Boston Red Sox 6–5Title change
21,570Mar 31, 2019Seattle Mariners beat Boston Red Sox 10–8Defense
22,503Apr 22, 2025Boston Red Sox beat Seattle Mariners 8–3Defense
22,504Apr 23, 2025Seattle Mariners beat Boston Red Sox 8–5Title change
22,505Apr 24, 2025Seattle Mariners beat Boston Red Sox 4–3Defense
22,552Jun 16, 2025Boston Red Sox beat Seattle Mariners 2–0Defense
22,553Jun 17, 2025Seattle Mariners beat Boston Red Sox 8–0Title change
22,554Jun 18, 2025Boston Red Sox beat Seattle Mariners 3–1Title change

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