These Arizona Fall League prospects are vying for 40-man roster spots

Call it a last-chance saloon in the middle of the desert.

The Arizona Fall League provides more than just an opportunity to see some of the game’s top prospects in one spot. It’s also the final place certain Minor Leaguers can prove they are deserving of a 40-man roster spot ahead of the Rule 5 Draft protection deadline.

Quickly for the uninitiated: Rule 5-eligible players are those who a.) signed when they were 19 or older and have been in affiliated ball for four or more seasons or b.) signed when they were 18 or younger and have been in affiliated ball for five or more seasons. In order to protect such players from being taken in the Rule 5 Draft -- a process designed to improve players’ MLB chances outside their current systems -- organizations can place them on their 40-man rosters by a certain date.

This year, the Rule 5 protection deadline is 6 p.m. ET on Tuesday, Nov. 19. The Rule 5 Draft is scheduled for Wednesday, Dec. 11, at the Winter Meetings in Dallas.

With those dates looming, some prospects have taken advantage of the extra playing time to help their chances. Here’s a breakdown of which Fall Leaguers might have played their way straight onto their respective 40-man rosters:

Colson Montgomery, SS, White Sox (No. 3/MLB No. 37)
For starters, no team would let a Top 100 overall prospect get close to the Rule 5 Draft, and that’s especially true of a rebuilding organization like Chicago. That gets to another level this year when the Rule 5 pool might not be so deep. High-school picks from the 2020 Draft are eligible this year, but there won’t be so many because of the shortened five-round process that year. Montgomery, meanwhile, is a rare prep pick from the 2021 Draft who is Rule 5-eligible this winter because he was 19 when he signed. The White Sox sent the 22-year-old shortstop to the Fall League in hopes of ending on a stronger note after he hit just .214 with a .710 OPS in 130 games for Triple-A Charlotte during the regular season.

Mission accomplished there: Montgomery posted a .511 on-base percentage and 6/10 K/BB ratio over 11 games in his second career AFL trip before it ended on Oct. 25. His three homers matched his 2023 Fall League total (after he dealt with oblique and back injuries) in nine fewer contests. The 6-foot-3 infielder got a lot of time at third base with Glendale but said he expects shortstop to be his full-time position in 2025 and beyond. The Sox were going to protect him anyway, but the move will look better now that he has wind in his sails again.

Denzel Clarke, OF, Athletics (No. 10)
No one who’s seen Clarke in Arizona would dare doubt his ferocity. The 24-year-old outfielder leads the Fall League with three triples, has gone 7-for-8 in steal attempts and has been a mainstay in center field for Mesa. He’s at least a plus runner and even better underway when the engine really gets going.

The big question in his profile remains his ability to make consistent contact; Clarke struck out at least 29 percent of the time at Double-A Midland in 2023 and ‘24. He’s running a 24.4 percent K rate against lesser fall pitching but has also shown more of a willingness to take a walk with a 16.7 percent BB rate and an even .500 OBP through 16 games. Only Major Leaguer Thomas Saggese (.524) has a higher on-base percentage this fall. Clarke’s power, speed and defense would get him long Rule 5 looks, and any approach improvements solidify his standing as a soon-to-be 40-man member for the A’s.

Robert Hassell III, OF, Nationals (No. 13)
Hassell’s first Fall League turn lasted only two games in 2022 due to a broken hamate. He slugged just .348 and collected two extra-base hits in 20 games in ‘23. His third has been a big improvement at a much-needed time. The 23-year-old has slashed .286/.360/.545 with four homers and 11 total extra-base hits through 19 games. What’s more, he’s had 37 batted-ball events recorded by Statcast; 21 (56.8 percent) have posted exit velocities higher than the hard-hit standard of 95 mph.

Getting his power to play in games has been a real problem for Hassell since the first hamate injury, and the Nats even sent him back to the complex for a time this summer to let his hand/wrist issues fully heal. He still might project best as a doubles-hitting fourth outfielder who can play all three positions, but Washington won’t want to let that slip away, especially given all the work the player and organization have put in to get him back to this status.

Josh Stephan, RHP, Rangers (No. 25)
Stephan was one of only 17 high-schoolers signed after going undrafted in 2020, and that decision to go pro instead of heading to Stephen F. Austin State sped up his 40-man clock, perhaps in his favor. The 23-year-old righty rebounded from a UCL sprain this summer to become one of the circuit's best pitchers, ranking second in both ERA (2.25) and strikeouts (21) while topping the loop in innings (20). He works with a pair of 92-94 mph fastballs, flashes a plus 82-85 mph slider and folds in an 85-89 mph changeup and a new 89-92 mph cutter, all while showing plus control when healthy.

📩 CLICK HERE TO SUBSCRIBE TO BEN'S BIZ

The Fall League is typically so hitter-friendly that any pitcher who can keep his ERA in check must be doing something right, and in this case, Stephan’s deepened arsenal and strong command could be enough to erase the previous injury concerns in the eyes of Texas.

Caleb Durbin, UTIL, Yankees
The 2021 14th-rounder out of Washington University in St. Louis stole 21 bases in the Fall League last year, good for the circuit's second-highest single-season total in history. This year? He’s already up to 23. No one else in the league has more than 11. The record is 24. Durbin certainly has the speed to push the envelope, and with a 40-man spot on the line, he’s willing to show off those wheels if it helps his case with the Yankees or another Rule 5 club. Those in the Bronx are certainly paying attention. General manager Brian Cashman has mentioned Durbin as a second-base candidate with Gleyber Torres hitting free agency. The 24-year-old didn’t post stellar exit-velocity data at Triple-A this year, prioritizing contact over pop, and he might fit best as a slap-and-dash hitter who moves around the diamond off the bench. (He’s played five different positions with Salt River this fall.) But even that has value as Cashman might have proved when he tipped his hand on one Nov. 19 decision.

Sammy Siani, OF, Pirates
As MLB Pipeline’s Jonathan Mayo noted, Siani flattened out his bat path in 2024 to give himself more time in the zone, and the result was his K rate dropping 31.7 percent in 2023 (after which he went unprotected and unpicked in the Rule 5 Draft) to 18.9 percent this season between High-A Greensboro and Double-A Altoona.

The 2019 37th overall pick has continued his work in the box this fall with positive results. He leads the league with a .406 average while ranking third in hits (26), fourth in OBP (.472), fifth in slugging (.594) and sixth in OPS (1.066). He’s also played all three outfield spots, getting more time in right where he has two assists, and his above-average speed should be helpful anywhere on the grass. The Pirates have only one Top 30 prospect in need of Rule 5 protection this year (No. 26 Omar Alfonzo), leaving space for a potential future fourth outfielder like Siani to get 40-man protection while his trajectory points upward.