Martinez, a member of the Mariners Hall of Fame after his outstanding career in Seattle from 1987-2004, was hired by former GM Jack Zduriencik to replace Howard Johnson as the hitting coach on June 20. At the time, the Mariners were batting .233 and averaging 3.4 runs per game through 68 games.
After Martinez joined the staff, the Mariners hit .260 and averaged 4.6 runs a game over the final 94 games. Dipoto said it became clear to him over the past two weeks that Martinez deserved to be part of the future plan.
"We had a handful of meetings with the Major League coaching staff and front office group," Dipoto said. "I did a lot of listening. And whether it's the obvious -- Edgar's history as a player and his character traits -- he's a wonderful human being.
"I played with Edgar many years ago in Puerto Rico and had a chance to watch how he handled himself," said Dipoto. "Now sitting with him and listening to him talk about players and break down players and see how clearly invested he is in making players better, I'm very excited about the opportunity to bring him back. This is where he wants to be, and that's a good thing."
Dipoto said neither Martinez nor Woodward have discussed new contracts yet, but "I think both guys would like to return."
Dipoto said he has no prior history with Woodward, but was impressed by the 39-year-old former Major League infielder. Woodward has been in the Mariners organization the past three years, initially as a Minor League infield coordinator, then as McClendon's infield instructor and first-base coach the past two seasons.
"He has the type of energy and passion I'm looking for and we'll value in our staff moving forward," Dipoto said. "I felt we were watching a real impact coach. With guys like [Robinson] Cano and [Kyle] Seager and [Chris] Taylor and [Ketel] Marte, he's made an impact on both young and veteran players in that infield."
Bench coach Trent Jewett, third-base coach Rich Donnelly, outfield coach Andy Van Slyke and bullpen coach Mike Rojas were told Friday they would not be returning. All four came to Seattle with McClendon when he was hired two years ago.
Waits also joined McClendon's staff as the pitching coach in 2014, but he already had been in the organization for three years as the Minor League pitching coordinator.
Prieto has been the team's quality control coach the past two years, but he also was in the organization prior to that as manager of the Pulaski rookie league club.