Why Dax Kilby Playing in the Arizona Fall League Is Perfect Proving Ground for His Development

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The New York Yankees didn't send their top minor league prospects to the Arizona Fall League in 2025, but they will be sending their biggest headliner this time around.
Last week, it was announced that shortstop Dax Kilby, the Yankees' No. 2 prospect and MLB Pipeline's No. 86 prospect, will be participating in the AFL this year. Kilby, who turns 20 years old in November, has impressed many with his hit tool and plate discipline in his first two MiLB seasons. While the sample sizes are small, Kilby has recorded more walks than strikeouts in both 2025 and 2026 with an on-base percentage well over .400 in 54 career minor league games.
Dax Kilby is #ValleyBound
— MLB's Arizona Fall League (@MLBazFallLeague) September 12, 2026
The @yankees No. 2 prospect and @MLBPipeline No. 86 prospect will be headed to the Valley this Fall! Kilby was drafted 39th overall by the Yankees in the 2025 draft. In 36 games this season, Kilby has hit four homers and stolen 12 bases. Kilby has… pic.twitter.com/hIPOlrC5TX
Kilby's participation in the AFL is in clear contrast to last fall, when the Yankees sent just two of their top-30 prospects (Bryce Cunningham and Cade Smith) to Arizona. However, sending Kilby to Arizona is consistent with how the Yankees have handled the other prospects they've sent there in the past.
Dax Kilby can make up for lost time in AFL
The common theme among the Yankees prospects who played last fall is that most missed time during the MiLB season due to injuries. Both Cunningham and Smith dealt with shoulder injuries in 2025, so playing in the AFL allowed them to at least partially make up for the time they lost during the regular season. These two pitchers have struggled this year (especially Smith), but they still rank among the Yankees' top-30 prospects.
In Kilby's case, he missed a huge chunk of the 2026 season with a hamstring strain and didn't make his season debut until July 24 with the Single-A Tampa Tarpons. The youngster picked up right where he left off with an .883 OPS, 10 extra-base hits, 12 stolen bases in 15 attempts, and 39 walks against just 31 strikeouts.
Nonetheless, with a grand total of 50 games played at the Single-A level across two seasons and the Tarpons playing in the FSL Championship, it's both too early and too late for Kilby to be promoted.
Dax Kilby with his 3rd HR on the season!
— Yankees Stats (@ChrisCoop_) August 27, 2026
105.6 mph / 18 deg, pulled on a 3-0 cutter over the RF fences.
AVG: .281
OPS: .882
Dax has been swinging with a lot more intention since coming back from injury, appearing to sell some contact for some more power and the results have… pic.twitter.com/ueKBXSEiWg
That's where the AFL comes in. If Kilby can continue to demonstrate his stellar on-base skills while developing more raw power during the fall, he can prove to the Yankees that he's ready to move up to the High-A Hudson Valley Renegades.
Dax Kilby SCORCHES a double to right center field off this low and inside righty to LHB sweeper.
— Yankees Stats (@ChrisCoop_) September 10, 2026
103.3 mph / 417 ft
First hit of the day for the Tarpons through three innings.
Paul GOATtierrez-Contreras had a 106 mph line out before pic.twitter.com/MlA9bc5JQE
Despite Kilby missing so much time this year, he at least managed to impress enough in limited time and can make his case for a promotion by playing well in Arizona. At the same time, the best way for Kilby to improve as a prospect is to play, and that's exactly what the AFL will give him.
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Joe Najarian is the Deputy Editor and a writer for the New York Yankees and New York Mets On SI sites. He got his bachelor’s degree in journalism with a specialization in sports from Rutgers University, graduating in 2022. Joe has previously written for Jersey Sporting News and for the New York Giants On SI site. You can follow him on Twitter/X: @JoeNajarian
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