The first major domino of 2025 MLB free agency has fallen — and it's not necessarily what we all expected. The Seattle Mariners have agreed to terms on a five-year contract with first baseman Josh Naylor, per ESPN's Jeff Passan.
The 28-year-old arrived in Seattle at the trade deadline last season and flourished, slashing .299/.341/.490 with nine home runs, 33 RBI and 19 stolen bases in 54 games as a Mariner. He was essential to their deep postseason run as well, posting an impressive .967 OPS with three home runs and five RBI in 12 October starts.
BREAKING: First baseman Josh Naylor and the Seattle Mariners are finalizing a five-year contract, sources familiar with the deal tell ESPN. The first major free agent to sign this winter goes back to Seattle, where he was beloved after joining the Mariners in a deadline trade.
— Jeff Passan (@JeffPassan) November 17, 2025
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Mariners officially re-sign Josh Naylor on five-year contract
This is huge for the Mariners. As of this writing, the exact terms of the deal are not released, but Naylor wouldn't come cheap. Seattle has struggled to hang with the major coastal markets in past free agency periods, but this proves the advantage of trading for a guy midseason and experiencing his impact on the field — and in the locker room — first hand.
"The Mariners made Josh Naylor their top priority entering the winter, and his excellence down the stretch got him a long-term deal to join Cal Raleigh, Julio Rodríguez and the Mariners’ rotation as a foundational piece," Passan wrote on X. "His energy was infectious. Seattle didn't want to lose it."
It can't hurt that Seattle was so, so close to cracking the AL pennant. Toronto barely escaped in Game 7, but this M's team is stacked, with elite pitching up and down the rotation, plus an increasingly potent offense — one that Naylor adds to in a huge way. If ever there was a time to stretch the checkbook and push your chips in, this is it. Credit to Jerry DiPoto and the Seattle front office for getting this across the finish line before a bidding war could heat up.
Mariners are lucky Josh Naylor didn't test the market
Even with the built-in familiarity that undoubtedly influenced this deal, it's a wee bit shocking to see Naylor fly off the board this soon. He was clearly the second-best first baseman in the 2026 free agent pool, at worst.
Pete Alonso, under the guidance of Scott Boras, is sure to drag things out in an attempt to drum up maximum interest and leave no stone unturned. There's a world in which Naylor waits for Alonso to sign and then capitalizes on the desperation of those who missed out, filling their vacant lot at first base.
Instead of letting the market plays out over time, however, Naylor committed to the Mariners and the Mariners committed to him. It's a significant milestone for the organization and proof that Seattle won't be going anywhere next season. This team very much intends to operate like a prime wolrd series contender, even if that means running up the tab.
Josh Naylor contract crystalizes Mariners' potent offense
Seattle has hung its hat on a lights-out rotation for years, but the offense has (not so quietly) caught up. Their 49 postseason runs were the most among non-Toronto or L.A. teams, with a 20-run margin over the next-best Detroit Tigers (29) and 23 more than the Milwaukee Brewers, whom the Dodgers dispatched in the NLCS.
The M's finished with 766 runs in the regular season, ninth most in MLB. They hit the third-most home runs (238). Seattle didn't hit for a high average (.244), but in today's MLB, that has never been less of a problem. It's all about cranking up exit velo and generating explosive outcomes. That is something the M's do as well as almost any other team, in no small part due to AL MVP runner-up Cal Raleigh and perennial All-Star Julio Rodríguez.
Naylor brings valuable balance to the lineup as a left-handed cleanup bat who generates consistent contact without slacking in the power department. He also tied for the third-most stolen bases in MLB (19) after his arrival in Seattle, becoming one of the most dangerous base-runners out there despite middling speed. He just plays smart and hard, which goes a long way in this league.
Seattle can still keep adding, too. This shouldn't be their last move, and it almost certainly won't be. There is room to improve on the left side of the infield, and in particular at third base, as Eugenio Suárez is expected to depart in free agency. The outfield depth chart isn't airtight either.
Seeing this newfound aggressiveness, the Mariners can't be counted out as a bidder in even the most extreme cases. This is an extremely desirable destination, due to both the on-field product and the natural charm of Seattle as a city and a fanbase. B/R also ranks the Mariners as the No. 1 farm system in MLB. DiPoto has a ton of trade ammo at his disposal, even after shelling out for Naylor and Suárez this past July.
Re-signing Naylor was step one toward a successful offseason. But this is merely the beginning. Special things are brewing in the PNW.