Sep 24, 2025; Toronto, Ontario, CAN; Boston Red Sox catcher Carlos Narvaez (75) celebrates with a win over the Toronto Blue Jays with third baseman Alex Bregman (2) as relief pitcher Payton Tolle (70) slaps hands with first baseman Nathaniel Lowe (37) at Rogers Centre. Mandatory Credit: Dan Hamilton-Imagn Images Dan Hamilton-Imagn Images

Red Sox Magic Number: How Boston Can Clinch First Playoff Appearance Since 2021

Originally posted on Boston Red Sox on SI
By Jackson Roberts | Last updated Sep 25, 2025 7:30 AM ET

Things were looking dicey last week, but the Boston Red Sox are suddenly on the doorstep of October.

Coming into the week, the Red Sox held a one-game lead for the final American League wild card spot over both the Cleveland Guardians and Houston Astros. But as the red-hot Guardians have kept winning, the Astros' fall-off has given Boston a nice cushion.

Following Wednesday night's 7-1 Boston win over the Toronto Blue Jays, plus the Astros' 6-0 loss to the Athletics, the Red Sox are so close to October baseball that they may not even have to take the field again to punch their ticket.

Red Sox's magic number is one

At 87-71 entering play on Wednesday, the Red Sox own a three-game lead on the Astros (84-74), plus the tiebreaker. Both teams have four to play, so as long as the Red Sox don't lose all four and the Astros don't win all four, Boston will be headed back to the playoffs for the first time since 2021.

The magic number is one, and Houston plays again at 3:35 ET to finish off it series with the A's. By the time the Red Sox hit the turf at the Rogers Centre for their 7:07 first pitch against the Blue Jays, they could already be safely into the playoffs. If the Astros win, the Red Sox would need to finish off the sweep to pop champagne in Toronto.

Fangraphs now gives the Red Sox a 99.5% chance to make the playoffs as of Thursday morning, after those odds dipped as low as 83.1% last week.

There are a few other clinch scenarios to dive into, so let's briefly break them down:

It's highly unlikely that the Red Sox can win the division. They'd need to win all four of their remaining games, have the Blue Jays (90-68) lose all four, and have the Yankees (90-68) lose at least three out of four.

They'd have to catch at least one of those two teams to host a Wild Card Series at Fenway Park, so the most likely scenario is that the Red Sox will head to Toronto, New York, Cleveland, or Detroit for a best-of-three set beginning on Tuesday.

Lastly, though t's not necessarily an advantage to grab the second wild-card spot instead of the third, but the magic number for Boston to finish ahead of Cleveland and/or Detroit and secure the AL's No. 5 seed is three.

This article first appeared on Boston Red Sox on SI and was syndicated with permission.

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