Arizona Fall League Preview: Chicago White Sox
By Gordon Kairis ·
The Chicago White Sox are sending nine prospects to the Glendale Desert Dogs this fall, a group that mixes upper-level bats, hard-throwing relievers and players working against roster deadlines. Caleb Bonemer, 80Grade's No. 2 White Sox prospect, headlines it and will spend part of the fall in center field. Nick Altermatt, a 27-year-old reliever who reached Triple-A, pitches in Glendale with the Rule 5 draft coming in December.
Caleb Bonemer's Versatility Test
Caleb Bonemer, a third baseman who turns 21 on October 5, is 80Grade's No. 2 White Sox prospect and No. 22 overall. He hit .251/.380/.550 with 37 home runs, 29 doubles and 92 RBIs in 2026 between High-A Winston-Salem and Double-A Birmingham, and 80Grade grades his power at 55. He played mostly third base and shortstop this season, and the White Sox started giving him reps in center field in Birmingham's final weeks; he opened the AFL in center on October 3. The fall will show whether his reads in the outfield can keep pace with a bat that is still vulnerable to elevated fastballs and breaking balls away, the main reasons behind his 27.1% strikeout rate.
Colby Shelton's Power Journey
Colby Shelton, a 23-year-old second baseman, had an uneven season at the plate, hitting .244/.338/.488 with 24 home runs and 34 doubles. He tore through High-A Winston-Salem (.339 in 31 games) before hitting .213 over 96 games at Double-A Birmingham. 80Grade grades his power at 55, and the home runs came back this year after a .141 debut in 2025, but contact against better pitching remains the question. His task in Glendale is to keep the power while putting more balls in play. He has played second base, third base and shortstop, which supports a utility profile.
Pierce George's Fastball Focus
Right-handed reliever Pierce George, 23, has a fastball that sits in the upper 90s and has reached 103 mph. Across 51 games, he posted a 3.56 ERA with 82 strikeouts in 65⅔ innings, climbing from Single-A Kannapolis to a one-game stop at Triple-A Charlotte. Strike throwing remains his concern: he walked 10.7% of hitters, a big improvement on 19.3% in 2025 but still the number to watch. In Glendale, he can sharpen his command of the fastball and get more work for his power curveball and cutter.
Mathias LaCombe's Command Challenge
Mathias LaCombe, a 24-year-old right-hander born in France, missed bats at four levels in 2026, striking out 31.3% of hitters, but he walked 25 batters over 49⅓ innings. His low arm slot gives him deception and fastball life, yet it also makes it harder for him to land the slider and splitter in the zone. The AFL gives LaCombe more innings to throw strikes with both pitches and build his case as a bullpen option.
Anthony DePino's Power Potential
First baseman Anthony DePino, 23, hit .262/.363/.481 with 25 home runs and 82 RBIs in 2026, spending most of the season at Double-A Birmingham after starting at High-A Winston-Salem. His contact against breaking balls and his defensive value are the areas 80Grade's report flags for improvement. The AFL will test the bat against more advanced pitching and show whether his glove can hold up at first base.
Grant Magill's Defensive Edge
Catcher Grant Magill, 25, caught in all 75 of his games in 2026 between High-A Winston-Salem and Double-A Birmingham. The bat lagged behind: he hit .237 with a 32.3% strikeout rate overall and .196 in 42 games at Double-A. Glendale gives him more time behind the plate and more at-bats against upper-level pitching.
Nick Altermatt's Roster Pressure
Nick Altermatt, a 27-year-old right-handed reliever, posted a 2.86 ERA over 56⅔ innings in 2026, splitting time between Double-A Birmingham and Triple-A Charlotte. He signed with the White Sox in 2022, has been eligible for the Rule 5 draft since December 2025 and is not on the 40-man roster. His AFL innings are part of the White Sox's evaluation as they decide whether to add him before the November protection deadline.
Quick Hits: Other White Sox in the AFL
Garrett Wright, 24, is a reliever with an upper-90s fastball who struck out 32.6% of hitters in 2026, but he also walked 15.3%, so throwing strikes is his priority in Glendale. He spent most of 2025 on the injured list, and the AFL innings add to a thin professional workload.
Jonathan Clark, 26, a right-handed reliever, posted a 4.10 ERA over 59⅓ innings in 2026, most of them at Double-A Birmingham, where he walked 14.2% of hitters. Cutting that walk rate is his focus this fall.
Bonemer is the centerpiece of the White Sox group, a 37-homer infielder who is now adding center field. Altermatt, Shelton and DePino all finished the season at Double-A or higher and give the club a closer look at upper-level depth before the 40-man decisions this winter.