The Diamondbacks are making a big move on the relief market. Arizona announced the acquisition of A.J. Puk from the Marlins for two prospects: corner infielder Deyvison De Los Santos and center fielder Andrew Pintar. The D-Backs designated lefty reliever Joe Jacques for assignment to create a 40-man roster spot.
It’s the second consecutive season in which Arizona makes a major addition to the late innings. The Snakes brought in Paul Sewald to lock down the ninth a year ago. Sewald is still holding down the closer role despite a rough stretch this month. Puk adds a high-octane southpaw to the setup group.
A former sixth overall pick by the Athletics, Puk broke through as a high-leverage reliever in 2022. Oakland dealt him to Miami for outfielder JJ Bleday in a swap of former top draft picks the following offseason. Puk fired 56 2/3 frames of 3.97 ERA ball with excellent strikeout and walk numbers during his first season in South Florida. He held the closer role for a stretch, picking up 15 saves and finishing 31 games altogether.
Miami could have been content to leave Puk in a late-innings role. First-year president of baseball operations Peter Bendix and his front office were curious about the possibility of stretching Puk back into the rotation role he’d occupied in college and during the early part of his minor league career. While the Spring Training results were promising, the starting pitching experiment proved a short-lived blunder.
The 29-year-old opened the season in Miami’s rotation. He took the ball four times and didn’t once make it through the fifth inning. Opponents teed off for 17 runs in Puk’s 13 2/3 innings as a starter. He walked 17 and hit a batter while recording just 12 strikeouts. The Marlins placed him on the injured on April 20, citing shoulder fatigue.
When they reinstated him a few weeks later, Miami abandoned the rotation maneuver and kicked Puk back into his customary short relief role. The results since then have been exceptional. The University of Florida product has turned in a 2.08 ERA over 30 1/3 innings out of the ’pen. He has punched out 33 of 114 batters faced while walking only six. Opponents are hitting .159/.204/.252 in that time. Puk has held seven leads in front of All-Star closer Tanner Scott (who is basically a lock to move before next Tuesday’s deadline himself).
Puk’s season stats are still weighed down by his disastrous few weeks in the rotation. Excluding his starting work paints the picture of an impact reliever. Over his season and a half in Miami, Puk carried a 3.31 ERA through 86 appearances when working out of the bullpen. He punched out 31.2% of batters faced compared to a tidy 5.3% walk rate. Puk has been particularly lethal to left-handed batters. Southpaws have hit .174/.215/.287 with 45 strikeouts and four walks over 123 plate appearances when Puk has pitched in relief. Righties have had a bit more success, particularly from a power perspective, but they’ve hit .236 with a modest .283 on-base percentage.
The D-Backs had been light on left-handed relief depth. Joe Mantiply was the only southpaw in Torey Lovullo’s bullpen. He has a 3.99 ERA behind a solid 48.2% ground-ball rate, but he doesn’t throw hard or record many strikeouts. Puk averages north of 95 MPH with his fastball and has a swing-and-miss slider that more comfortably plays in the late innings. Mantiply can serve as the second lefty in the hierarchy, while Brandon Hughes is on optional assignment to Triple-A.
Puk is playing on a $1.8MM salary in his first season of arbitration. The Diamondbacks are taking on a bit less than $700K for the stretch run. He’ll go through the arbitration process twice more before hitting free agency during the 2026-27 offseason. Puk doesn’t have the gaudy save totals that arbitrators tend to value from relievers, so he should be a generally affordable bullpen piece for the next couple years.
Miami brings back a pair of mid-tier prospects in their first of what should be a handful of deadline deals. De Los Santos is the more highly-regarded of the duo. He’s a right-handed hitting infielder who has elevated his stock with a monster season in the upper minors. Baseball America’s JJ Cooper tweets that De Los Santos would have ranked eighth on the outlet’s forthcoming update of Arizona’s top 30 prospects. Pintar would’ve landed 21st on that list.
The D-Backs signed De Los Santos out of the Dominican Republic five years ago. He immediately intrigued evaluators with his power upside but struggled to make contact in the low minors. He played his way to Double-A by age 20 and connected on 20 homers there last season. Yet he also struck out at a 26% clip and only managed a .297 on-base percentage. The Diamondbacks left him unprotected for the Rule 5 draft and briefly watched him depart the organization. The Guardians snagged De Los Santos in the Rule 5 and carried him on their 40-man roster during Spring Training.
Cleveland decided at the end of camp that they couldn’t devote a bench spot to a development project. The Guards returned De Los Santos to Arizona after he cleared waivers. The Snakes sent him back to Double-A Amarillo for a second straight year. De Los Santos obliterated the level, hitting .372/.426/.696 with 14 homers in 38 games. He hasn’t tailed off much since being promoted to Triple-A Reno. De Los Santos has 14 more homers over 49 Triple-A contests, and he’s running a .289/.338/.588 slash.
There’s still a fair bit of risk with De Los Santos’ profile. Scouts have never loved his defense at third base. Arizona has used him mostly at first base this season, suggesting that’s where he projects as a big leaguer. He remains an aggressive hitter who isn’t taking many walks. That’s a difficult profile to pull off, but De Los Santos clearly has impact power that could fit in the middle of a lineup if he hits his ceiling. Miami will need to put him on their 40-man roster at the start of the offseason to keep him out of the upcoming Rule 5 draft. There’s a good chance they call him up at some point after the deadline, particularly if they manage to find a taker for Josh Bell in the coming days.
Pintar, 23, was a fifth-round pick out of BYU back in 2022. A righty-swinging center fielder, he has spent the bulk of the season in High-A. Pintar hit .304/.403/.516 with nine homers and nearly as many walks as strikeouts over 57 games. Arizona had promoted him to Double-A a couple weeks ago. Pintar has above-average speed and has improved his offensive profile with his strong showing through the season’s first few months.
As for Jacques, he’ll likely land on waivers in the next few days. Arizona claimed him off waivers from the Red Sox in April. He only pitched once for them at the MLB level. The 29-year-old southpaw has a 5.60 ERA over 27 1/3 innings in the minors this season. He made his MLB debut with Boston last season and worked to a 5.06 ERA across 26 2/3 frames.
The D-Backs could look into adding a starting pitcher and/or an offensive upgrade before Tuesday, though a high-leverage reliever has seemed their priority for weeks. Miami will certainly remain active on the trade market. Beyond Scott, they’re likely to move Jazz Chisholm Jr. and try to offload some of Bell’s contract. They could field offers on others relievers like Andrew Nardi and Calvin Faucher, starter Trevor Rogers, and outfielders Jesús Sánchez and Bryan De La Cruz. The Fish are in full rebuild mode and don’t have many players who’ll be categorically off the table.
Ken Rosenthal of the Athletic first reported the Diamondbacks were acquiring Puk. Craig Mish of SportsGrid reported the Marlins were acquiring De Los Santos as one of two prospects. USA Today’s Bob Nightengale identified the second prospect as a position player, while Ari Alexander of KPRC-2 was first to report it would be Pintar. Alexander reported the Jacques DFA.
Image courtesy of USA Today Sports.