Also returning are bench coach Dave Jauss, hitting coach Jeff Branson, first-base coach Nick Leyva, third-base coach Rick Sofield, assistant hitting coach Jeff Livesey, Major League coach Brad Fischer and bullpen catcher Heberto Andrade.
"I like having them back," manager Clint Hurdle said. "I believe our players like having them back. There's been continuity. We've all grown together. You're not catching anybody up. You're not plugging anybody in fresh and new. They're aware of the culture and the environment, our coaching technique.
"I'm very happy for them. They've earned this opportunity. Very happy for their families, as well. It's always nice to know that your work is appreciated."
In 2014, the Pirates extended the contracts of Hurdle and general manager Neal Huntington through '17, with club options for the '18 season.
"We are very pleased to maintain the continuity and quality of our Major League coaching staff through at least the 2017 season," Huntington said in a statement. "This is a group of quality, talented baseball men who make our organization better each day."
The Pirates' decision to retain Searage, who had been in the final year of his contract, will come as a particular relief to Pittsburgh fans worried about possibly losing their "pitcher whisperer." In his sixth full season as Pittsburgh's pitching coach, Searage has been the driving force behind turnarounds from starters like Francisco Liriano, A.J. Burnett, Edinson Volquez and J.A. Happ.
The rest of the staff may not receive as much national attention as Searage, but they've all played a role in the Pirates' success over the past three seasons.
The Bucs value their coaches' ability to appreciate and understand the front office's philosophies -- many of them driven by advanced metrics and data -- and communicate those to their players.
"That's part of the reason they were extended," Hurdle said. "The buy-in is real. If there's no buy-in, they wouldn't be here. It's pretty simple, and we've had some real candid conversations here that we're going to do things this way. There are non-negotiables here -- what we believe in as an organization, some core values and philosophies."
Sofield, for instance, has helped the Pirates' outfielders adjust to playing shallower than in previous years. In addition to guiding John Jaso's transition to first base and Jung Ho Kang's acclimation to American baseball, Leyva is involved in the Bucs' infield shifts.
"Their opportunities to make the presentations to the players are their own," Hurdle said. "That's the beauty of their personalities. Everybody's presentations matter and count, and they're all different. I think that's one of the things that keeps the players engaged."