Sep 14, 2025; Seattle, Washington, USA; Seattle Mariners players dance after the win over the Los Angeles Angels at T-Mobile Park. Mandatory Credit: John Froschauer-Imagn Images John Froschauer-Imagn Images

Mariners' Magic Number To Clinch Playoff Berth After Crucial Rangers Loss

Originally posted on Fastball on SI | By Jackson Roberts | Last updated Sep 16, 2025 11:00 AM ET

The Seattle Mariners may have been enjoying an off-day in Kansas City on Monday, but it was still a productive day for the team.

Seattle is looking to clinch its first playoff berth since 2022 and its first American League West division title since 2001. Monday helped them toward that first objective, while slightly hurting them in regards to the second.

With the Houston Astros' 6-3 defeat of the Texas Rangers, here's a look at where the standings, plus the Mariners' magic numbers to clinch the division and a playoff berth, stand:

Mariners' magic number to clinch postseason: 9

Texas is now virtually tied with the Cleveland Guardians in the standings, and the Mariners are fortunate enough to own the tiebreaker over both teams. The Mariners are 82-68, the Rangers are 79-72, and the Guardians are 78-71.

That means Seattle's playoff magic number is nine, which it technically was entering play on Monday, since the Guardians were idle. However, the de facto "magic number" to finish ahead of the Rangers is now eight, which could matter because Texas has an easier remaining schedule than Cleveland.

The Rangers and Guardians also play each other to finish out the season, so depending on whether the Mariners take care of business ahead of schedule, they could be forced to take a strong rooting interest in that series.

Mariners' magic number to clinch division: 12

On the other side of the coin, Houston beating Texas slightly shrank the Mariners' odds of clinching the division. The Astros trailed the Mariners by half a game at the conclusion of play on Monday.

It's safe to say that this weekend's three-game series between Seattle and Houston at Daikin Park will play an outsized role in determining the division champions. Both teams have relatively soft schedules the rest of the way, but there's always a chance someone could stumble.

As the Mariners begin a three-game road set with the 75-75 Kansas City Royals, they can be assured that destiny is in their own hands if they take care of business. But there's also still a long way to go.

More MLB: Mariners' George Kirby Has Message On Astros, Rangers Amid Tight AL West Race

This article first appeared on Fastball on SI and was syndicated with permission.

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