Martinez, 52, replaces Howard Johnson, who will be reassigned in the organization, most likely as a roving instructor in the Minor League system.
"For the last three years I've been thinking I wanted to get back in the game," Martinez said. "Obviously I wanted to do it with the Mariners because I've played my whole career with them. I do think this is the right time. I haven't seen as much talent in the Mariners for a long time. I think we have the right talent, the right manager and coaching staff. I think it's a great opportunity for me and I'm excited about it."
General manager Jack Zduriencik said the move became obvious as a team with high expectations struggled to a 31-37 start. The Mariners rank last in the American League in runs per game and batting average, despite adding considerable star power in the past two years -- Robinson Cano, Nelson Cruz, Austin Jackson and Mark Trumbo -- to some highly touted youngsters, including Dustin Ackley and Mike Zunino, who have not lived up to expectations.
"In the end, it just wasn't happening for us," Zduriencik said. "If you look at the numbers alone, we were disappointed in how the offense was performing. We all clearly believe this is a better offensive club than what we were producing. As a result, and with our relationship with Edgar over the years, I think his resume speaks for itself."
Indeed, the street outside Safeco Field is named Edgar Martinez Way, and there is Edgar's Cantina just down the left-field line for patrons to eat and drink at during games. Martinez spent all 18 of his Major League seasons with the Mariners, posting a lifetime line of .312/.418/.515, with 514 doubles, 309 home runs and 1,261 RBIs.
The two-time American League batting champ will now try to teach his trade as a coach, a process he began in recent years as an occasional guest instructor during Spring Training with the Mariners, and this past year as a special assistant working with Minor Leaguers.
"We all know how he became the hitter he became, the things that he did to become -- in our view -- a Hall of Famer, and as a result, we hope he brings that to the table," Zduriencik said. "We're very confident that the things Edgar will speak to our players about and bring to the table will be a real positive impact."
Martinez said a positive approach is one of the things he craved as a player and will impart on Seattle's hitters.
"I didn't want to hear what I'm doing wrong," Martinez said. "Most players know they're doing wrong. It's more, 'How can I fix it?' Focus on positive information that they can start feeling good about their swing and their game. I think Lee Elia was great at that. He'd always have something positive to say."
Manager Lloyd McClendon, a hitting coach for the Tigers for seven years, before taking over the Mariners last season, said Martinez shares many of his own philosophies in that regard.
"In conversations I've had with Edgar about hitting in the past, his passion for the game, and obviously, what he accomplished, his presence in the locker room, his knowledge. I think all those things came into play," McClendon said. "He's proven that he knows what he's doing, he knows what he's talking about. I'm hoping that it can jump-start us and help us quite a bit."
That didn't make Saturday's decision any easier for McClendon, however, as he said sitting across from the table and telling his friend Johnson that he was being removed wasn't pleasant.
"The fact is, we haven't performed up to our capabilities probably for a season-and-a-half," McClendon said. "I certainly think this club is better than it's shown from an offensive standpoint. I said this when I took the job and I think it holds true in this instance, we're either the victims or the beneficiary of how our teams perform on the field. In this case it was unfortunate that it cost HoJo his job."
Martinez will be the sole hitting instructor for the Mariners, with Andy Van Slyke -- who had been working as an assistant to Johnson -- moving back to his former position as strictly the outfield coach.
Martinez was in his familiar No. 11 uniform for the Mariners' game Saturday night against the Astros.
Johnson, 54, was in his second season as the Mariners' hitting coach and third in the organization. Martinez becomes Seattle's 11th hitting coach in the past 14 seasons.