The 2025-26 offseason has started quite early — a major first base target signed just weeks after free agency opened, bucking the trend of the last few offseasons dragging into spring training.
The Seattle Mariners and Josh Naylor have agreed to a reunion on a five-year deal, first reported by MLB insider Jeff Passan on November 16. Ari Alexander of WHDH 7News reports that the deal is in the $90-100 million range, but the price has not been officially released.
The Mariners traded for the first baseman from the Arizona Diamondbacks at the 2025 trade deadline, and he was a stellar fit for them during their playoff chase. Naylor batted .299/.341/.490 with an .831 OPS over 54 regular season games with Seattle. He hit 29 doubles and 20 homers on the season, and stole 30 bases.
The Boston Red Sox are reportedly considering an upgrade at first base and Naylor was among the best available in this year's class. Boston wasn't linked to him quite as often as it is Pete Alonso, and for good reason.
The Mariners' reunion with Josh Naylor is good for the Red Sox, despite his talents at first base
The Red Sox mostly need a jolt of power in their lineup, and while Naylor's 20 homers would certainly help, they could use a bigger boost than that. Boston missed out on 35 homers after trading Rafael Devers to the San Francisco Giants last season, and it should at least make up for that loss. Alonso slugged 38 homers last season and Cody Bellinger, who can also play first base, hit 29. If Triston Casas bounces back well from his knee injury, there's a good chance he could hit more than 20 home runs in a full season (he's never posted one in the major leagues before, however).
Naylor also doesn't hit to left field often, so he wouldn't make much use of the Green Monster. Alonso is a righty, he'd bring more balance to the batting order, and the Monster would be his best friend, although he can hit it out of the park everywhere.
The Mariners' reunion with Naylor could also take them out of other potential free agency pursuits that could've affected the Red Sox. They'd been tabbed as a potential fit for Alonso if Naylor departed in free agency. Now, Boston has less competition in the longtime Mets' market.
Seattle is also in the market for a third baseman after it traded for Eugenio Suárez, an impending free agent, at the deadline to take up the hot corner during its playoff run. The Mariners aren't usually big spenders, so a deal with Naylor could lessen its motivation to spend big on a potential deal with Alex Bregman or Suárez, who could be a backup for the Sox if Bregman signs elsewhere.
Naylor is a great first baseman who proved his fit with the Mariners during the second half of the 2025 campaign and during their playoff run, but his fit with the Red Sox was questionable. After his reunion with his latest team, the Red Sox's competition in both corner infield markets could be slimmer.