On December 3rd, 2018, the Mariners traded Jean Segura, Juan Niasco, and James Pazos for Carlos Santana and J.P. Crawford. At the time, most fans saw the move as a harbinger of the losing seasons to come—the Mariners were entering a rebuild, and this was one of the first steps taken as the front office tore down their 89-win roster after yet another failure to make the postseason. Everyone seemed to focus on Jean Segura and Carlos Santana more than Crawford, treating him as more of a long-shot “change of scenery” candidate than a big trade headliner. After spending years as one of the top prospects in Baseball, Crawford was coming off a very disappointing season, looking like a potential bust as he struggled with injuries and pressure to perform. There were plenty of doubts, especially amongst his former team’s front office, as to whether he would be able to bounce back in the future. And for a while those doubts seemed justified, as Crawford’s first two seasons in Seattle were a mixed bag of gold-glove defense and lackluster offense.
But that didn’t last long. From 2021 onwards, J.P. Crawford has been the most valuable Mariners Shortstop since A-Rod left for Texas, solidifying a position that had been a weakness for most of the previous two decades. From 2001-2018, Mariners starting shortstops were worth a total of 21.9 fWAR, an average of 1.21 fWAR per season. Since J.P. Crawford took over in 2019, he has accumulated 17.1 fWAR for an average of 2.13 fWAR per season. He hasn’t been a superstar level player—in fact, he hasn’t made an all-star team yet despite having a couple very good seasons—but after years and years of searching for a long-term answer at SS, Crawford has been a foundational piece of the M’s roster. In fact, Crawford’s breakout coincided perfectly with the M’s recent string of winning seasons. 2021 was the M’s first 90-win season since 2003, and it was also Crawford’s first season above 2.0 fWAR.
But J.P. brings more value than just his stats. Coming in at the beginning of the rebuild, Crawford has been there for all the struggles along the way. Mitch Haniger, Kyle Seager, and J.P. Crawford were the only constant guys in the lineup during those bleak seasons, as the roster turned over every year. They were all leaders of sorts—but Seager was the vet and undisputed main leader during his tenure. When Seager retired after that crazy 2021 season, it appeared as though Mitch Haniger filled the void left behind. But it wasn’t just Mitch that filled that void. In his famous letter to Mariners fans in October 2021, Haniger named J.P. Crawford as one of the tone-setters on the team; one of the guys holding others responsible. And that group, along with Paul Seawald, Marco Gonzales, and others, laid the foundation this 2025 team stands on. They believed that the 2021 season was just the beginning.
That made 2022 even sweeter, as Crawford’s leadership role grew significantly, they broke the drought, and ushered in a new crop of talent that included Cal and Julio. Haniger’s departure that offseason made J.P. the undisputed #1 leader of the locker room, and by all accounts, he has done a fantastic job in carrying on the torch. Now the longest-tenured player on the team, he has contributed well to their playoff push and remains a respected leader of the club.