D-backs' bullpen showing stability amid strong turnaround

For several seasons, the Diamondbacks have been unable to solve the puzzle that is their bullpen.

Even with one of the top run-producing lineups and solid starting pitching to boot, the reliability of the bullpen has held Arizona back in recent years. Entering 2026, the concern over the relief corps lingered, even after the additions of Paul Sewald, Taylor Clarke and Jonathan Loáisiga.

A little over a quarter of the way into the campaign, and the results have been … better.

"I think by and large, they've done a good job,” D-backs general manager Mike Hazen said. “They're throwing strikes and they're going right at hitters, and we're playing pretty good defense.

“It's hard for me to go back and tease out what part was the bullpen and what part was the defense last year, and we've played better defense, and we're throwing the ball better and throwing more strikes, and we're getting better results.”

Indeed, Arizona has benefited from much-improved defensive play, entering Thursday ranked eighth in MLB in defensive runs saved (12) and fourth in outs above average (six). But the D-backs’ bullpen hasn’t been the liability that plagued the club during a serious postseason push in 2024 and a disappointing '25 season riddled with injuries to key contributors like A.J. Puk and Justin Martinez.

More importantly, the group appears to be hitting its stride, even after a heartbreaking loss Wednesday at Texas.

Since May 1, the Diamondbacks’ 1.99 bullpen ERA is the lowest mark in MLB. Opposing batters are hitting just .173 against them in that same 12-game stretch.

So what has changed?

Arizona has been better at protecting leads, particularly in close games. A byproduct of the D-backs’ bullpen struggles in the past has been demoralizing losses due to blown leads late in games. Of their 20 wins this season, nine of them have come in contests decided by two runs or fewer.

Stability in the back end has made a massive difference, with Juan Morillo -- who has been the unit’s biggest standout -- Ryan Thompson and Clarke helping bridge the gap to Sewald, who has looked a lot like the closer he was in the second half of 2023, when the Trade Deadline acquisition played a vital role in the D-backs’ run to the World Series.

That quartet alone has combined for a 2.65 ERA over 68 innings.

D-backs manager Torey Lovullo has also been able to mix in others, such as Kevin Ginkel and Loáisiga, in high- and low-leverage spots and has been mostly successful in doing so to this point.

“I think we've had a couple of guys emerge as very trusted backend guys,” Hazen said. “I think the guys in the front have thrown the ball really well. Torey's done a good job of making sure everybody stays hot and gets work in multiple types of situations. Clarke has been jumping in and out of leverage. Thompson's been jumping in and out of leverage. Ginkel has been doing that. So I think that's good.”

Brandon Pfaadt, who was moved from the rotation to the bullpen to clear a spot for Merrill Kelly when he returned from the injured list in April, has been a valuable multi-inning option. The hope is to find a balance between keeping Pfaadt stretched out while also deploying him in the right situations. Pfaadt ended an eight-day hiatus since his previous appearance with three scoreless innings and five strikeouts against the Rangers on Tuesday.

"We obviously want to get him back in the mix,” Hazen said.

While the group has had more success against right-handed hitters as opposed to left-handers (.633 OPS vs. RH, .702 OPS vs. LH) -- which was viewed as a potential concern after entering the season with an all right-handed bullpen -- Brandyn Garcia was called up from Triple-A Reno on May 1 to give Arizona some flexibility against lefty batters. Garcia has not allowed a run in 5 2/3 innings.

The bullpen will receive a significant boost if Puk and Martinez -- who are both rehabbing from elbow surgery -- are able to rejoin the club later this season. Puk is tracking toward a return around the All-Star break, while Martinez could be activated sometime after that.

It’s been far from perfect, but the D-backs have fared all right without them early on. Even the slightest improvements have made a difference.

"The bullpen has been very consistent all year long,” Lovullo said. “It's been our carry tool, and very consistent. The offense, the bullpen and a little bit of starting pitching, and we got off to a nice little start. But the bullpen has been real good all year long, for sure."