Josh Naylor is heading back to the West Coast.

ESPN’s Jeff Passan is reporting that the first baseman has agreed to a five-year deal with the Seattle Mariners. Naylor is the first big-name free agent off the board this winter.

The financial terms of the deal are not yet known at this time, or if there are any opt-outs involved.

After spending the last five years with the Cleveland Guardians, the Mississauga, Ont. product was traded during the 2024/2025 offseason to the Arizona Diamondbacks in exchange for RHP Slade Cecconi. At the 2025 trade deadline, the Diamondbacks moved the slugger to the Mariners, acquiring pitchers Brandyn Garcia and Ashton Izzi.

Across both teams, Naylor authored a .295/.353/.462 slash line with 20 home runs, 92 RBIs and a career high 30 stolen bases, to go along with a .816 OPS through 543 at-bats. He posted similar numbers with both teams, although he stole more bases with Seattle (19) compared to Arizona (11). After joining Seattle, Naylor posted a 2.2 bWAR with 10 doubles, nine home runs, and 33 RBIs to the tune of an .831 OPS. At the plate, the 28-year-old posted a 13.7 percent K rate, ranking in the 80th percentile.

In the postseason, Naylor was a force to be reckoned with at the plate. Although he struggled initially against the Detroit Tigers in the ALDS, he finished the series with two three-hit games in Game 4 and Game 5, with two doubles to help secure the next round spot against the Blue Jays. From there, he continued to impress, collecting 10 hits and posting a .417 average and a 1.273 OPS through 24 at-bats, including three home runs and five RBIs in the eventual series loss.

At first base, Naylor amassed a +4 DRS and made just five errors while posting a .995 fielding percentage and a +2 OAA.

Naylor was one of the main free agents from the Mariners roster this winter, along with third baseman Eugenio Suarez, infielder Jorge Polanco, catcher Mitch Garver, and reliever Caleb Ferguson.

With his long-term deal, Naylor joins a core group for the Mariners consisting of runner-up AL MVP Cal Raleigh and outfielder Julio Rodriguez.

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