SAN DIEGO -- The Padres are locking up one of their key bullpen arms for a long, long time.

Right-hander Robert Suarez has agreed to a five-year deal to remain in San Diego, sources told MLB.com on Thursday. The club has not yet confirmed the deal, which is pending a physical.

The deal is worth $46 million over the duration of the contract and features a player opt-out after the first three years.

Suarez established himself as the team's primary setup man for closer Josh Hader, posting a 2.27 ERA in his first season in the big leagues. The 31-year-old Suarez had spent the previous five years pitching in Japan before the Padres signed him to a two-year deal last offseason.

That deal, however, featured a player option, which Suarez declined Monday.

Memorably, Suarez's 2022 season ended when he allowed the two-run home run to Bryce Harper that sent the Phillies to the World Series. But Suarez was utterly dominant throughout the postseason prior to that moment, particularly in the Padres’ NLDS victory over the Dodgers.

He established himself as the team's primary setup weapon, but it's entirely possible the Padres view Suarez as their closer of the future, with Hader only under contract through the end of next season.

From the moment Suarez signed with San Diego, he was viewed as potential closer material, sporting a fastball in the high 90s and a putaway changeup. He struggled early while dealing with some knee trouble but posted a 1.48 ERA in the second half.

"Thanks to the help of my teammates, my coaches and this staff, I was able to make adjustments and got better and better as I went on," Suarez said at the end of the season.

Considering how well he pitched down the stretch, Suarez's opt-out was something of a formality. But the Padres and Suarez always expressed a strong desire for a reunion.

Suarez rejoins a deep Padres relief corps that also features Hader, Luis García, Tim Hill and Steven Wilson. On top of that, Drew Pomeranz is expected to return from a left elbow injury next season, and San Diego might also look to bolster the middle innings with an additional signing or two.

Meanwhile, the team remains in discussions to bring back right-hander Nick Martinez, according to sources. Martinez’s contract also featured an opt-out, which he exercised on Thursday. But there’s mutual interest in a reunion.

Martinez pitched in the bullpen down the stretch, but the Padres are viewing him primarily as a starter next season.

“We’ve talked about giving him the opportunity to start,” A.J. Preller said Wednesday at the General Managers Meetings in Las Vegas. “That’s important to him. But also he’s shown this year he’s got the numbers to pitch out of the bullpen. He filled a valuable role for us this year.

“The conversations with him have been getting a sense of what he wants to do, but also the need of our ballclub. Starting, for us, is something we really want to explore with him and something he wants to do. We also know throughout the year, depending on what happens in the offseason, he’s got the ability to do some different things.”

Considering the arms at the back end of their bullpen -- Suarez now included -- the Padres would appear to have a much bigger need in their rotation, with Mike Clevinger and Sean Manaea hitting free agency on Thursday afternoon.