Report: Mariners to make first major signing of offseason

The Seattle Mariners had reportedly considered retaining first baseman Josh Naylor to be their top priority in free agency. Their wish has reportedly come true.

In the first major signing of the 2025-26 offseason, ESPN's Jeff Passan reported that Naylor and the Mariners are finalizing a five-year contract. According to Ken Rosenthal of The Athletic, the deal will become official once Naylor passes a physical. Financial details of the agreement have yet to be disclosed.

The Mariners acquired Naylor on July 24 with a pair of pitching prospects heading back to Arizona. He had put together a solid showing for the Diamondbacks at that point, posting a .292/.360/.447 batting line over 394 plate appearances, hitting 11 homers and 19 doubles while stealing 11 bases. Mariners first basemen had combined for a .223/.293/.376 batting line through July 24, ranking 23rd in the majors with a .668 OPS.

Josh Naylor helped transform Seattle Mariners lineup over final two months

Naylor changed that narrative from the moment he arrived in Seattle. He thrived in the Mariners lineup, posting a .299/.341/.490 batting line with nine homers and 10 doubles over 210 plate appearances. His 19 steals over the final two months of the season not only led the Mariners but were more than his career best in a full season. He was the Mariners' third most valuable player after the trade with 1.8 bWAR, trailing catcher Cal Raleigh and outfielder Julio Rodriguez.

He made his presence felt in the postseason as the Mariners came agonizingly close to their first World Series appearance. Naylor had a .340/.392/.574 batting line over 51 plate appearances in October, hitting three homers and two doubles. 

That playoff run made a reunion possible. After dealing with financial limitations over the previous two offseasons, ownership had given the green light to increase payroll for 2026. Signing Naylor, who had been a major factor in the Mariners' success in 2025, became a necessity.