Diamondbacks Add Bullpen Depth With Former Astros Reliever

The Diamondbacks add a relief arm.

Feb 20, 2025; West Palm Beach, FL, USA; Houston Astros pitcher Shawn Dubin (66) poses for a photo at the Houston Astros media day. Mandatory Credit: Reinhold Matay-Imagn Images | Reinhold Matay-Imagn Images

The Arizona Diamondbacks are adding some depth to their bullpen. According to their transaction logs, the D-backs have signed former Houston Astros and Baltimore Orioles right-hand reliever Shawn Dubin to a minor league contract.

Dubin will report to Triple-A and join the Reno Aces, adding some depth to the D-backs' minor league bullpen. Dubin's signing is backdated to December 19, 2025.

Related Content: Diamondbacks Sign Former Yankees Reliever

Arizona Diamondbacks Sign Shawn Dubin

Sep 6, 2025; Baltimore, Maryland, USA; Baltimore Orioles pitcher Shawn Dubin (62) throws during the sixth inning against the Los Angeles Dodgers at Oriole Park at Camden Yards. Mandatory Credit: Daniel Kucin Jr.-Imagn Images | Daniel Kucin Jr.-Imagn Images

Dubin, the 30-year-old righty, was originally selected in the 13th round of the 2018 MLB Draft by the Astros. He spent the next several seasons working his way up, eventually reaching Triple-A in 2021. He's been up and down between MLB and Triple-A ever since.

Though he got his first taste of the majors in 2023, Dubin saw his first large share of innings in the 2024 season. Over the course of 31 appearances (45.1 innings) with Houston in that season, he pitched to a decent, albeit not eye-popping 4.17 ERA and 3.72 FIP.

He made 23 appearances for the Astros in the 2025 season, but struggled to the tune of an ugly 5.63 ERA over the course of 23 appearances, 25.2 innings. On August 23, he was designated for assignment by the Astros, and subsequently picked up off waivers by the Orioles.

Dubin made seven appearances for the Orioles, pitching to a 3.38 ERA in eight innings. Though he posted an overall ERA north of 5.00 between the two clubs in 2025, it's worth noting his expected ERA (xERA) was much lower, at 3.74.

Dubin has a starter's arsenal, despite pitching primarily in relief for the past several seasons. He throws a mid-90s four-seam, with an even split between a sweeper, sinker, curve and changeup — with an occasional cutter, as well.

He also has familiarity with the Pacific Coast League — the league in which the Reno Aces Reside — having pitched there in parts of the last four seasons. The offense-heavy environment can break down any arm, but he managed a 1.04 ERA in nine appearances there in 2025.

While Dubin doesn't immediately seem like an arm that will contribute at the major league level for Arizona right away, there's a decent chance the standard churn of a 162-game season might necessitate his services, given his relative level of success at the MLB level.

The D-backs still have not added anyone to their major league bullpen as of this writing, however. Arizona's roster is in dire need of relief help as they await the return of Justin Martinez and A.J. Puk, but have mostly kept their signings to small, minor-league additions.