Diamondbacks have a young back-end of the bullpen to build around

Diamondbacks pitching coach Brian Kaplan recalled “one of the most impactful meetings” Arizona had in 2026 was back in spring training, when the bullpen got together in a room at Salt River Fields.

“We said, ‘Hey, what are some of the characteristics of a really strong bullpen?'” Kaplan described. “Just wanted to lay out who we were, and what we want to stand for and the things that we held in value.”

That meeting, he felt, got the group on the same page early.

Between veteran additions such as Jonathan Loaisiga and Taylor Clarke and the growth of young pitcher with quality stuff in Brandyn Garcia and Juan Morillo, Arizona’s bullpen became the strength of the team.

Even without Justin Martinez until August, with trade acquisition Kade Strowd making no meaningful impact and A.J. Puk not throwing a single pitch, the D-backs assembled a group that was unified and flexible, buying into what Kaplan called a strike-throwing culture.

The Diamondbacks did not even have a set closer for the second half of the year, and that uncertainty was embraced as opposed to overwhelming. It was a group that looked capable of helping the D-backs in October had they gotten there.

“They all came together, became a family, had each other’s backs, it was really fun to see,” Kaplan said.

Building a bullpen is one of the most volatile and difficult jobs a front office has, but in this case, the Diamondbacks finally hit on a young core of high-octane relievers to build around in Garcia, Morillo and Martinez.

The bullpen ERA was middle-of-the-pack 4.07, but that does not tell the story of this group.

Arizona had four relievers make at least 57 appearances with an ERA under 3.00. The unit’s win probably added (percentage change in a team’s chance of winning) was fourth in MLB, as the D-backs’ bullpen led the league in walk rate and finished top 10 in WHIP, exit velocity and hard hit percentage.

Veterans such as Nolan Arenado and Corbin Burnes went right to the bullpen when asked about what went right for the D-backs despite their disappointing playoff miss.

“We probably have one of the best bullpens in the league this year,” Martinez said. “So hopefully we continue to do what we did this year, and next year will be better if we keep working, putting everything together.”

“I think it’s a bullpen that all teams would like to have for the future,” Morillo said via Spanish interpreter. “We have to dedicate ourselves to keep working, to be in harmony and the good thing is that we have the confidence to support each other every time we go out on the field.”

The Diamondbacks went into the season in a tough place with the bullpen, expecting to get Puk and Martinez back from elbow surgeries at some point while hoping a group of veterans on one-year deals could help fill the gaps. Paul Sewald did as closer throughout the first half before his performance fell off, while Clarke and Loaisiga provided quality innings and stayed healthy throughout the season.

But what took the bullpen up a level was the emergence of Garcia and Morillo.

This was Garcia’s rookie year after he got his feet wet in 2025, while Morillo was a rookie last season. Both can pump high heat, and they have quality secondary stuff to keep hitters honest — especially Garcia’s sweeper and Morillo’s changeup.

The question was a matter of their control, and Garcia’s lack of strikes in spring training caused the D-backs to start him in Triple-A and enter the season with no lefties.

Both pitchers honed in their stuff dramatically, which led to stellar results.

Garcia made 57 major league appearances and delivered a 1.93 ERA, 0.74 WHIP and 31.3% strikeout rate.

Morillo pitched in 70 games with as 2.24 ERA, 1.06 WHIP and 28% K rate.

“Just mentally being there, just getting the reps, this is my first full year in the big leagues other than the first month,” Garcia said of trusting his stuff. “So it was just having those reps, having that confidence in myself. Finding out who I am as a pitcher was important, too. Not trying to be somebody else, not trying to compare myself to other people that have done it before me. It’s just being Brandyn Garcia.”

“Coming here last year, that helped me gain experience,” Morillo said. “This year, I think was able to improve in my command. It was the big jump.”

Garcia is 26 years old, Morillo is 27 and Martinez is 25. They are under team control through at least the 2020s.

Arizona acquired Garcia in the Josh Naylor trade to Seattle last summer. Morillo was a minor league free agent pickup after the 2024 season, a Los Angeles Dodgers cast-off. Martinez has been with the Diamondbacks’ organization since he was a teenager.

The Diamondbacks are going to have the difficult task of building depth around them, along with managing their health. Garcia and Morillo had never made that many appearances in a season and Martinez is coming off major surgery.

Loaisiga expressed interest in returning but is a free agent, as is Clarke, Puk, Kevin Ginkel and Ryan Thompson.

Ginkel sat in the dugout looking out for several minutes after Arizona’s season finale on Sunday, and he already made a thank you post on Instagram. Perhaps Andrew Saalfrank helps after losing a season to shoulder surgery, or maybe another young arm or two emerges next spring.

But to start with a back end of exciting, controllable arms with big stuff — especially with one lefty — is a stronger position to build out the bullpen than the club has operated on in the recent past.

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