Previewing the Arizona Diamondbacks Bullpen

Up until a few days ago, the Arizona Diamondbacks' bullpen looked set for Opening Day, with the exception of the last roster spot perhaps. But the recent injuries to Kevin Ginkel and Jordan Montgomery have altered plans significantly.

Ginkel, who was going to occupy a key role as a right-handed setup man with some save chances when the matchups were right, will instead go to the 15-day IL with right shoulder inflammation. He will be out at least that long, and might require some additional ramp-up time depending on how long he's shut down for.

As of Wednesday afternoon Torey Lovullo could not say exactly when Ginkel's throwing program would resume again.

Montgomery meanwhile will miss the entire season due to needing Tommy John surgery. That news also broke on Tuesday morning. The veteran left-hander with a $22.5 million dollar contract was slated to begin the year in the bullpen in a long-relief role.

Partly in response to these injuries the Diamondbacks signed left-hander Jalen Beeks to bolster the pen. Mike Hazen said that he made this move now as once MLB rosters are set it's much more difficult to add players. With these moves then we can preview the Diamondbacks bullpen for 2025:

Opening Day Bullpen

Justin Martinez - RHP

The fireballing Martinez will bring his 100 MPH fastballs along with a devastating splitter and slider to the late innings, and frequently get the opportunity to close games. Martinez posted a 2.48 ERA with 91 strikeouts in 72.2 innings. Martinez just signed a five-year, $18 million dollar contract extension with club options that could keep him with the team through 2031.

A.J. Puk - LHP

The towering left-hander will join Martinez in getting save chances depending on the matchups. Puk throws a mid- to high-90's fastball and devastating slider. He'll mix in some changeups as well. As a reliever Puk has been dominant in his career, including a 1.32 ERA in 27.1 innings for the D-backs last year after a July 25 trade with the Miami Marlins.

Ryan Thompson - RHP

The veteran sidewinder will see an increased role on the right side of matchups with the absence of Ginkel. Now 33 years old, Thompson pitched to a 3.26 ERA in a career high 66.1 innings in 2024. He had a 2.04 ERA in the first half and 5.06 ERA in the second half however.

Joe Mantiply - LHP

The 34-year-old Mantiply is back for his seventh season with the D-backs. An All-Star in 2022, things have been a bit bumpier for the lefty the last couple of years. In 99 combined innings across 2023-24 he has a 4.20 ERA despite a 3.04 FIP. He's always been tough on lefties, who have batted just .227 with a .585 OPS against him in his career.

Shelby Miller - RHP

Miller came into camp as a non-roster invitee on a minor league contract, but pitched impressively to win a spot on the Opening Day roster. Featuring a mid-90s fastball, slider and splitter, Miller is not the same pitcher he was during his early career stint as a starter with the team.

He is able to mix speeds and command his offspeed, and is not as fastball reliant as he once was. He still gets plenty of swing-and-miss however, as evidenced by his 11 strikeouts in 6.2 innings of work in Spring Training.

Bryce Jarvis - RHP

Fully recovered from a sprained elbow suffered in July last year, Jarvis will look to reprieve his role as an innings eater in the bullpen. The right-hander posted a 3.19 ERA last year in 44 games, 59.1 innings. He gave up just two runs in 9.1 innings this spring while striking out 13 batters.

Ryne Nelson - RHP

Nelson lost out in the starting pitcher competition, giving way to Brandon Pfaadt after a couple rough spring outings. This despite being the team's most effective starter over the second half last year.

From July 2 through the end of the season Nelson posted a 3.05 ERA with a 3.14 FIP in 83 innings. He will start the season a long reliever, and Torey Lovullo will try to keep him as stretched out as possible should he be needed to fill in as a starter again.

Jalen Beeks - LHP

Newly-signed Beeks was just released by the Houston Astros on March 22. He pitched last year for the Colorado Rockies and Pittsburgh Pirates, posting a league-average ERA+ of 100 (4.50 ERA). Now 31 years old, he's entering his seventh MLB season. He throws a 95 MPH fastball along with a changeup to use against right-hand batters, and a cutter to attack left-hand batters.

40-Man Roster Depth

Right-hander Drey Jameson and left-hander Kyle Nelson were both optioned out to Triple-A Reno. In Jameson's case Torey Lovullo said he still had some boxes to check in his comeback from Tommy John surgery, such as pitching in back-to-back games and multiple innings.

Nelson had a rough spring overall working his way back from Thoracic Outlet Surgery, but pitched a scoreless inning against the Cleveland Guardians in an exhibition game on Monday.

Non-Roster Depth

Non-roster pitchers who could find their way on to the major league roster at some point during the season are as follows:

Right-handers Kyle Amendt, John Curtiss, and Juan Morrillo.

Left-handers Jose Castillo and Kyle Backhus are possibilities as well.

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