Diamondbacks Sign José Castillo to Minor League Contract

The Diamondbacks add left handed depth with a minor league signing.

Arizona Diamondbacks pitcher Jose Castillo (66) during spring training workouts at Salt River Fields at Talking Stick in Scottsdale on Feb. 15, 2024. / Rob Schumacher/The Republic / USA TODAY NETWORK

The Arizona Diamondbacks have re-signed José Castillo on a minor league deal to bolster their minor league relief core.

Castillo will return to Reno for the second straight year, after spending 2024 with the D-backs' Triple A affiliate. There he posted a 4.35 ERA in 21 games and 20.2 IP, providing some much needed depth.

As a left handed reliever Castillo could be on the short list to recieve a callup should any of the Diamondbacks' MLB southpaws go down with injury. It should be noted however that the team currently has a strong group to fill the role, since the acquisition of A.J. Puk has bolstered the leftie relief core.

Other left-handed options who will play roles at the MLB level include Joe Mantiply who has been a staple in the D-backs bullpen since his All-Star campaign, and Kyle Nelson. Nelson missed most of 2024 with Thoracic Outlet Syndrome but was tendered a contract earlier this off-season.

Andrew Saalfrank who played a role in the Diamondbacks' 2023 World Series run could also potentially see time in the majors when he returns from suspension. He has been out since it was revealed that Saalfrank violated the league's Gambling policy, but he will be eligible to pitch in 2025.

José Castillo first signed with the Tampa Bay Rays and began his professional career. As a rookie in 2018 with the Padres he posted a 3.27 ERA in 38 innings, but has just two major league innings since then.

For the Diamondbacks this is clearly a depth move in the event of disastrous injury. In 2024 the team dealt with repeated hits to the Major League pitching staff and General Manager Mike Hazen is doing his best to bolster potential bullpen options.

Castillo's relatively low 0.4 Home Runs/9 and solid 9.1 K/9 in a very hitter-friendly Reno environment could have made him a decently attractive option to retain in the organization. While Castillo may not be a big impact player for the D-backs in 2024, expect him to be a reliable option that could be called upon throughout the year.

Make sure to stay locked in to all things Arizona Diamondbacks ON SI as we continue to bring you offseason coverage, and the newest information on the D-backs.