Two Rising Pitching Prospects Promoted to Triple-A Reno

The Diamondbacks have promoted two of their top pitching prospects, right-hander Dylan Ray and left-hander Spencer Giesting, to Triple-A Reno.

It comes as no surprise that the two pitchers have gotten the aggressive promotion to Triple-A. Both Ray and Giesting are Rule 5 eligible after the season as players taken in the 2022 MLB Draft out of college. With both pitchers now in Triple-A, they're almost certain to be added to the 40-man roster in the offseason.

Ray, 24, has spent each of the past three seasons with Amarillo. Injuries have slowed down his progress, but a midseason mechanical adjustment has allowed him to take off. In May, Ray won all five of his starts, all quality starts, pitching to a 2.03 ERA with 35 strikeouts, and three walks. In those five starts, he never walked more than two or struck out fewer than six.

Diamondbacks' farm director Chris Slivka noted that Ray has altered his delivery to resemble the one he used in his 2023 breakout season. His velocity is up, and his breaking pitches are sharper and more consistent, leading to a significant rise to the No. 7 spot in our midseason prospects ranking.

Giesting, 23, has come on strong over the past two seasons. The left-hander has gotten off to a strong start, pitching to a 3.67 ERA/3.95 FIP in 10 starts with Amarillo. He's posted excellent strikeout (24.4%) and walk rates (7.9%) in 2025, despite his home ballpark inflating offense. Giesting has climbed up to the No. 12 spot.

While pitching in the Pacific Coast League presents its own challenge, it's not a unique one for the two pitchers. Their home ballpark of Hodgetown plays similarly to many of the parks in the PCL, including Greater Nevada Field in Reno.

With Ray and Giesting now at Triple-A, we should have public Statcast data on the two pitchers and how their arsenal works. Both pitchers project as bottom-of-the-rotation starters but could debut at some point in the 2025 season.