Four Key Takeaways From Week 2 of the Arizona Fall League for D-backs Prospects
Here are four important takeaways from the D-backs prospect contingent in the Arizona Fall League.
The second week of the Arizona Fall League is complete, with the Salt River Rafters going 3-2 on the week.
The Arizona Diamondbacks' prospects got plenty of runway in the second week. Drey Jameson, Yordin Chalas, and Kyle Amendt each got two outings. David Hagaman made his second start of the fall. Jansel Luis started four more games, while Jack Hurley and Kenny Castillo started two games each.
Here are four important takeaways from the D-backs prospect contingent in the Arizona Fall League.
Drey Jameson's Still Has Electric Stuff
Save for one really awful outing against Peoria on October 10th, Jameson has looked electric in the Arizona Fall League. The league doesn't offer much of a challenge for a player who should be on the inside track for a bullpen spot next spring.
While he has a 10.80 ERA in four games, he's been scoreless in three of them. All of his walks came on October 10th; in his other three appearances, he tossed a scoreless inning each time with a total of three strikeouts.
Jameson's 4-seamer velocity has been over 98.0 MPH in his three scoreless appearances. With bone spurs in his elbow causing him to miss much of the season, it's a great sign. Combined with a four-pitch mix (sinker, slider, and changeup have flashed plus quality), he has the stuff to be a back-end arm.
I'm not sure how much longer Jameson will pitch in the fall league. The D-backs had a lot of their personnel watching the game, including Rehab Pitching Coordinator Tom Gorzelanny. With four successful appearances, they could pull the plug and allow Jameson to have a normal offseason and compete for a bullpen spot.
Yordin Chalas Has Looked Solid
Chalas was one of the more intriguing prospects in the D-backs system. So far, he's living up to that billing. He's pitched three scoreless outings and recorded a save on Saturday's tripleheader.
The velocity has held pretty well, averaging 95-97 MPH on the sinker. Interestingly enough, opposing hitters have been very aggressive at attacking the pitch. Of the 21 sinkers that Chalas has thrown in the fall, 18 have generated a swing. Opponents are 2-for-7 with no extra-base hits against the sinker.
Chalas has talked about throwing his slider and splitter more. So far, 11 of his 34 pitches have been those two. The slider and splitter have each generated one swing. The former induced a whiff from Reds prospect Cam Collier, the latter a soft ground ball that dropped 5 feet in front of home plate for an easy out.
The pitch data is a very small sample size, but it will be interesting to see how this plays out in a larger sample. How he starts 2026 could determine if he is a late-season call-up candidate for the bullpen.
Michael McDermott
Jansel Luis is Very Streaky
Luis has nine hits in the Arizona Fall League in nine games. However, the hits have come in bunches. He's recorded three multi-hit games but also six hitless games in the first two weeks.
Luis' second week in the Arizona Fall League was mostly down, although he salvaged it with two solid games at the end. He finished with two hits in their weekend game against Glendale out in Goodyear, ripping two line drives up the middle for singles.
He's shown a ground ball problem, especially to his pull field, when batting left-handed. Of 31 batted balls in the fall, Luis has pulled 14 ground balls. He's only pulled two balls in the air, both being line drives.
In the fall league so far, Luis has hit the ball hard but not at the right launch angles. 15 of his 31 batted balls recorded an exit velocity of 95.0 MPH or greater, but nine of them had a negative launch angle.
I'll have to recheck the chase rates for the D-backs switch-hitting prospect, but I wonder if there's an approach problem or a timing issue. He posted a 34% chase rate with Hillsboro in 2025, increasing to 47% with two strikes.
His defense has been a problem. He's committed multiple errors at shortstop and isn't quite as clean at third base. It's a small game sample size, and he probably didn't get as many reps at third base as he should have during the season. It's something that will take time to improve. Consistency will be the next step as he continues to refine both his swing path and defensive versatility
Michael McDermott
David Hagaman's Stuff Ticks Down in Second Start
The key for a starting pitcher is learning how they compete without their best stuff. Hagaman had that problem in his second start. His velocity was down a full tick on all four of his pitches, and his command was not quite as sharp.
The stat line is uglier than he looked out there. He surrendered three runs in 2.2 innings, striking out two and walking one. He threw 52 pitches on the day, 32 for strikes. Overall, he competed well on the day and deserved a better fate.
However, he gave up singles on a well-placed chopper that got through the right side (86.7 MPH exit velocity and a -26° launch angle) and a pop-up the third baseman (Braylen Wimmer) lost in the shadows behind the mound. The final run he allowed came after he threw his final pitch, as Isaac Stebens had quite the meltdown.
Michael McDermott
Further Reading
Michael McDermott
