Five D-backs Prospects Who Improved Their Standing in April

With the first month of the minor league season complete, there is a sufficient sample size to evaluate pitchers and hitters in the Diamondbacks farm system. These five prospects really stood out during April.

Cecconi didn't make the D-backs Opening Day rotation but found another opportunity when injuries struck. The right-hander has put together four quality starts between Triple-A Reno and the major leagues out of seven, showing an improved slider and changeup compared to last season.

Cecconi told me that his main goal was to add more velocity to his slider to get it above 84 MPH and that he picked up Merrill Kelly's changeup grip. His slider is averaging 85 MPH in his two major league starts, with a whiff rate of 33.3%, and the changeup has proven to be an effective putaway pitch against lefties.

Cecconi will graduate from the next prospect list, but his long-term outlook is much more optimistic about sticking in the rotation. With a mid-90s fastball with a lot of arm-side run, a plus slider, and a plus changeup, he's looking like a future middle-of-the-rotation arm and could reach that level fairly soon.

Del Castillo has hit the ground running in his second year with Triple-A Reno, batting .337 with 11 doubles, five home runs, and a .987 OPS. It's shaping up to be a breakthrough season for the catcher prospect, who's found his power stroke in the last two seasons. While he may be in line for some minor regression, his batted ball data supports the breakthrough. His xBA is .319 and his xwOBA is .389, both very strong marks.

Del Castillo profiles as a backup behind Gabriel Moreno, but as a left-handed bat would serve as a good compliment. He's got enough athleticism and mental makeup to stick behind the plate, but a below-average arm could be a problem against base stealers if he doesn't have a quick release. He's worked hard to improve his catcher defense since joining the organization.

Once a third baseman prospect who struggled defensively, the D-backs have finally moved De Los Santos to first base. The shift to a less demanding defensive position has coincided with an uptick in offense. In his first 21 games, he's batting .376 with seven home runs and a 1.112 OPS. The strikeout rate sits at an acceptable 23.7% in his first 93 PA. His strong series in Frisco earned him Texas League Player of the Week for April 22nd-28th.

In the offseason, D-backs general manager Mike Hazen admitted evaluating hitters in Amarillo and Reno is difficult when explaining his decision to keep De Los Santos off the 40-man roster. Perhaps getting a taste of the big leagues and competing for a roster spot is exactly what he needed to improve after a disappointing 2023 season. He's still only 20 years old, and could very well develop into the middle of the order slugger the team needs.

He profiles as a .240-.250 hitter at the MLB level that can provide 30-40 home run power. He has light tower power to all fields, which should help him with his approach at the plate once he realizes he doesn't have to pull everything to do damage. If this is the breakout year we all expected from De Los Santos, he could be an option at first base in the second half of 2025 and beyond.

Conticello wasn't on my radar for prospects entering the season, but his start with High-A Hillsboro is impossible to ignore. In his first 21 games, the 20-year-old infielder is slashing .322/.422/.513 with four home runs. Accounting for the extreme pitcher-friendly environment of Ron Tonkin Field, FanGraphs rates his offense to be 79% better than the league-average player with a 179 wRC+.

There are some swing-and-miss concerns with Conticello, who has a 24% strikeout rate, but he also draws walks at a high clip of 12%. It'll be something to monitor throughout the season, in order to determine if this is a hot start or the beginning of a legitimate breakout.

Grice isn't necessarily pitching deep into his starts, as he's racked up just 11 1/3 innings across four appearances (three starts), but the results have been effective. He's struck out 22 of the 46 batters faced (47.8%) and walked only two. Despite never pitching more than 3 2/3 innings in a single appearance, he's recorded three appearances of at least five strikeouts.

Grice utilizes a low-90s sinker, a slider, and a changeup, with the ability to command the pitches fairly well. He's not stretched out to a regular starting workload, having just thrown 58 pitches in his last start, but he's slowly ramping up. His stuff and command is definitely too advanced for Low-A, so it wouldn't be surprising to see Grice be one of the first prospects promoted in the organization.