Will it be any better in 2025?
The Arizona bullpen has been an Achilles’ heel for almost as long as Mike Hazen has been in charge. We’ve previously documented where Arizona’s relievers ranked in various areas: the team has been below major-league average, regardless of whether you look at ERA, FIP, xFIP or fWAR, every season since 2019. Last year, the team was in the bottom third by all four metrics. Given how narrowly they missed the post-season, it’s no exaggeration to say the bullpen cost the team a playoff spot last year. Nothing shows this more clearly than a 59% save percentage. That ranked the D-backs equal 26th: three of the four teams below them had the worst three records in the majors for 2024 (Rockies, Marlins and White Sox).
Hazen will hope to do better this year, constructing a bullpen which can protect leads, and also keep games close enough to give the offense a chance to come back. However, there won’t be many new faces down there for 2025. Kendall Graveman is the only addition to the team to this point, and by Opening Day, it’s going to be virtually at 18 months since Graveman last pitched in a meaningful game. On the other hand, the return of Drey Jameson after Tommy John surgery could become a key factor, even if his last major-league appearance was even longer ago, back on July 6, 2023. The plan appears to be to make him a full-time reliever, and he faced live batters on Wednesday, with no apparent health issues.
Provisional bullpen
If the season started today, the eight members of the bullpen might be something like this (in alphabetical order):
- Kevin Ginkel
- Randall Graveman
- Drey Jameson
- Joe Mantiply
- Justin Martinez
- Ryne Nelson
- A.J. Puk
- Ryan Thompson
Right now, Fangraphs Depth Chart puts both Jordan Montgomery and Shelby Miller in our bullpen, but I would be quite surprised to see either there on Opening Day. As we discussed last week, Nelson right now looks likely to be one of the odd man out of the rotation candidates. It’s possible the team might opt to move both him and Brandon Pfaadt down to Reno, to keep them stretched out as starters there. If so, then Bryce Jarvis could be the recipient of the long relief position in the bullpen instead. The above configuration would give manager Torey Lovullo two left-handers, in Mantiply and Puk, with the former likely getting more mid-game opportunities.
Roles
What’s going to be interesting is how Lovullo uses them, particularly in regard to ninth-inning save situations [a reminder: only the ninth inning can lead to a save, but save situations and blown saves can occur at any point, once the starter has left a game] Ten different players got saves for Arizona last year, but the prime one, Paul Sewald, is no longer with the team, having signed a one year, $7 million contract with Cleveland. However, of the pitchers in the bullpen listed above, all six who pitched in 2024 (so not Graveman and Jameson) picked up at least one save for the D-backs. Martinez led with eight, ahead of Ginkel’s who had five.
It doesn’t appear Graveman will be in the closer mix, at least initially. Asked about that after the signing, Hazen said “I wouldn’t think so, but I wouldn’t say no to anything either. I would just say it’s a big expectation for where he is… My guess is that would probably be a tall ask right out of the shoot.” But Lovullo has kept his cards close to his chests when asked about the position. While he would prefer to anoint someone in the job, he won’t do so purely for the sake of it: “I’ve got to make sure that wherever we’re handing out these spots… it’s for the best reasons for this team to go out and win a baseball game. So I’ll adhere to that, and I’d like to, but I’m not going to force it.”
Puk and Martinez would seem to be the leading candidates, but Lovullo acknowledged it can be hard to make decisions based on preseason performances, when games don’t matter, and pitchers may be trying out new things. “I think spring training is always a big challenge for an underreaction, an overreaction, being overwhelmed, underwhelmed. It’s a little bit of a challenge, so we look at it a little bit differently. We don’t necessarily base it off the results, but sometimes we do. It just depends on who the competition is and what it looked like in the moment. We want to see guys make pitches, shape pitches, have mound presence, and we want to get to know the guys.”
Depth
Obvious statement is obvious: you’re not going to get through the entire season with eight relievers. In fact, you’ll be lucky to get through about the middle of April. Last year, the first bullpen transaction happened on April 17, when Logan Allen was called up from Reno. So depth matters. Last year, Arizona used 25 different relievers, excluding position players, or more than three entire bullpens. Now, some didn’t throw much. But even if you cross off the top eight by innings worked, there were still 193.1 innings thrown by everyone else. And for Arizona, those did not go very well in general. The “tail” combined for an ERA of 5.87, and without the resulting six losses… Well, I needn’t draw you a picture.
This is an area where the rotation factors in, because the more our rotation pitches, and pitches effectively, the less stress on the bullpen. Starters have been going less deep generally. Remember Lovullo “asking for our starters to go 21 outs”? That happened barely one in ten games last year (17), with an average only fractionally above 15 outs. It was still not much below league average. But hopefully, the improvements to the rotation, such as the addition of Corbin Burnes, will have a trickle-down effect, by helping avoid the need for the bullpen to work as much. Lovullo can then pick and choose the best reliever for the situation, rather than being limited to whoever has an arm which isn’t falling off.
This might be an area where the team will struggle. While reliever volatility is undeniably a thing, the front eight have all had recent(ish) success. But after that, the fall-off might be quite steep. There are a couple of arms who should be reliable. I already mentioned Jarvis, and if Kyle Nelson comes back healthy after his thoracic outlet surgery in April, he could be an important piece. But the non-roster invitees with major-league experience aren’t names to inspire confidence, e.g. Miller, Scott McGough, José Castillo. The team may end up having to roll the dice on rookies like the two Kyles, Amendt and Backhus, throwing them into the fire and hoping they can learn on the job.
It’s not a problem unique to Arizona, of course. No team has 24 quality relievers (though I haven’t checked the Dodgers ‘pen…). But the sheer number of players needed over the course of a season is a challenge, and I fully expect it’s going to be another roller-coaster year for D-backs fans, in relation to the team’s corps of relievers. We’ll see if Hazen and co have finally cracked the code, because even mediocrity would be a help.