Ken Phelps never really got the chance to be an everyday player in his career, mostly used in platooning situations, but that makes his days in baseball sound so basic. 

Dave Valle made his Major League debut in 1984 with the Seattle Mariners, and he would play for the M's infrequently over the next three seasons before he would play the lion's share at Catcher in 1987.    

The fact that Leon Roberts had a Major League career at all was impressive, considering that he withheld poor vision from his teammates and management.  Regardless, he fought for a spot in Baseball, and his best years happened in Seattle.

After being drafted in the 12^th Round of the 1997 Draft, Joel Pineiro would reach the majors in 2000, and made it to the Mariners starting rotation in 2002. 

Tom Paciorek made his debut in the Majors in 1970 with the Los Angeles Dodgers, and he saw little action with L.A. when he played there until 1975.  The Atlanta Braves had him next but released him in May of 1978, and by that time, he was 30 and had never been more than a platoon player.  The Mariners would sign him days later, and the First Baseman remained as a platoon player, but he would see more action in 1980 and would have 114 Hits.  That was good, but in 1981, he had an unexpected season.

After playing a decade in Japan with Yokohama, Kazuhiro Sasaki was a 32-year old rookie in Seattle, and with a decade of real experience, he easily won the 2000 American League Rookie of the Year Award.  The former Central League MVP would finish third in the AL with 37 Saves.

Mitch Haniger played five seasons in the Majors with Seattle, the team that he will likely be forever most associated with.

From Canada, James Paxton was a fourth round pick who would play collegiately at the University of Kentucky.  Paxton debuted in 2013 and had four starts, winning three of them.  Over the next three seasons, Paxton was often on the disabled list, and he had a pedestrian 15-15 record, but by 2017, he was healthy and was able to show what he could do.

Omar Vizquel is not primarily associated with the Seattle Mariners, but the player who would become one of the best defensive infielders ever would begin his career in the Pacific Northwest.

After four years in the Majors,  Brice Bochte would sign with the Seattle Mariners as a Free Agent and went on to have the best run of his career.  

Franklin Gutierrez was not a superstar in the Majors, but his best years by far were his time in Seattle.

Jeff Nelson was with the Seattle Mariners for three different runs, and while he was a four-time World Series Champion with the New York Yankees, it is with Seattle where he will always be most associated with.

Julio Cruz was an original Seattle Mariner, who had been in the California Angels farm system for three years.  Cruz saw action immediately as a rookie n 1977, and as a sophomore, he was affixed as their starting Second Baseman.  While he was a light hitter (only 17 Home Runs, with a Mariners Slash Line of .243/.327/.307), Cruz was a quick player who knew what to do once he was on base.  He would steal 59 Bases in 1978, and would hit the 40 SB mark in the four years after. 

A World Series Champion as a rookie in 1978 with the New York Yankees, he would be traded two seasons later to the other side of the country and standings when he went to Seattle.

Phil Bradley played the first five years of his Major League career with the Seattle Mariners, and it was in the Pacific Northwest where he posted his best numbers. 

Carlos Guillen's career took off with the Detroit Tigers, but his Major League career began in Seattle.

J.J. Putz made his Major League debut with the Seattle Mariners in 2003 for three games, and in 2004 and 2005, he had a role in the bullpen appearing in 118 Games.  In those two years, Putz was just another arm, but after adding a splitter to his arsenal, and winning the closing job, 2006 would see him reborn.

In terms of infield defensive versatility, Jose Lopez is right at the top of the list for the Seattle Mariners.

When learning that his son (erroneously) was dead from George Steinbrenner, Frank Costanza’s first response was:

“What the hell did you trade Jay Buhner for?  He had 30 Home Runs, over 100 RBIs last year!  He’s got a rocket for an arm!  You don’t know what the hell you’re doing!”

Erik Hanson played his first six seasons in the Majors with the Seattle Mariners, where he would start 143 of his 145 Games with a 56-54 record.