A member of the 3,000 hit club, Adrian Beltre, would collect 751 of his 3,166 Hits with the Seattle Mariners. 

After a dozen seasons in the Japanese League, Hisashi Iwakuma made his way to the United States, specifically with the Seattle Mariners, the only team he would play for in Major League Baseball.

An All-Star for three of his four seasons as a Seattle Mariner, Nelson Cruz provided substantial power numbers for his duration in the Emerald City.

If you have the nickname of "Mr. Mariner," it stands to reason that the player in question is an important player in franchise history.