San Francisco Giants Non-Roster Invitee Showcasing Major League Stuff on Mound

A San Francisco Giants non-roster invite pitcher is making a strong case to be under consideration for Opening Day.

Apr 5, 2024; Arlington, Texas, USA; Houston Astros relief pitcher Miguel Diaz (39) pitches during the game between the Texas Rangers and the Houston Astros at Globe Life Field. | Jerome Miron-Imagn Images

The San Francisco Giants have made their first cuts of the spring training, and a few surprising names were on the list, either optioned to the minor leagues or reassigned to minor league camp.

Top prospect Bryce Eldridge was reassigned after one booming home run. Former top prospect Marco Luciano and pitcher Mason Black were both optioned as well.

One of the players who made it through the first round of cuts and remains with the Major League club in camp is pitcher Miguel Diaz.

He made his MLB debut on Apr. 17, 2017 with the San Diego Padres and ended up pitching 41.2 innings as a rookie. Diaz remained with the Padres through 2021, as he didn’t play during the COVID-shortened 2020 campaign.

Upon his return to the mound in 2021, he looked to have found something.

He pitched an effective 42 innings for San Diego that season with a 3.64 ERA.

The sample size isn’t huge during the subsequent three years. He spent 2022 and 2023 with the Detroit Tigers, pitching 17.2 innings before playing with the Houston Astros in 2024, where he pitched one frame.

But his production remained solid, and he landed a deal with the Giants this winter as a non-roster invitee for spring training.

Diaz has his work cut out to make the Major League team, but at the very least, he is garnering some attention.

In his most recent outing against the Padres, he pitched one inning, allowing two hits and striking out three. He had a proStuff+ score of 103 and generated an eye-popping 54.5% whiff rate.

Leading the way for him in his arsenal is one of the best changeups that has been featured this year during the exhibition season.

He threw it 52.2% of the time against San Diego and dominated.

The pitch registered a proStuff+ score of 120 and an elite whiff rate of 66.7%.

I now understand why he throws his changeup 50% of the time pic.twitter.com/qB1nc5eGjg

— Pitch Profiler (@pitchprofiler) March 5, 2025

Currently projected to be on the team’s Triple-A team, Diaz is someone worth keeping an eye on.

He could be in the mix as a middle reliever for the big league team should an injury arise or if he continues showcasing pitch numbers of that magnitude.

Promotions are always made during the season, and he is putting himself squarely into contention to be called up to San Francisco at some point during the year.