A Full Breakdown of the San Francisco Giants prospects headed to the Arizona Fall League

The Arizona Fall League rosters have been released this week with a lot of intriguing prospects on each team. There are six teams full of prospects from Major League teams that will play starting October 6th. I’ll be writing an article and making Twitter posts about each team’s roster. This will cover the prospects on the San Francisco Giants who will be on the Scottsdale Scorpions this fall. The team will consist of players from the Houston Astros, New York Mets, Washington Nationals, and the Detroit Tigers as well.

San Francisco Giants:

Ricardo Estrada LHP: After four straight seasons pitching in the Dominican Summer League Estrada made the jump to the states and has looked great this season. Starting in the Complex League where Estrada threw 35.1 innings to a 1.53 ERA he absolutely dominated with a 31.7% strikeout rate and 5% walk rate. He was promoted to Low-A and struggled in 37.2 innings. He had a 2.63 ERA but a 4.85 FIP due to his strikeout rate dropping to 18.5% and walk rate jumping to 12.3%. Estrada has gotten a ton of ground balls going back to his time in the DSL so when he did have bad games it wasn’t blow up outings only giving up at most 2 earned runs at a time. There’s no public data on Estrada but his fastball reportedly sits around 93 mph. His best pitch is supposedly a high 80s changeup that when located gets a lot of whiffs. He’s already 23 years old and is now Rule 5 eligible even though nobody's going to take him. It's almost time for the Giants to make a decision on Estrada and they’re testing him this fall.

Spencer Miles RHP: Drafted in the 4th round of the 2022 draft Miles has barely played since joining the Giants organization. After the draft he pitched in 7.1 innings between the Complex League and Low-A in 2022. He missed the entire 2023 season and came back in June 2024 pitching 7.1 innings in the Complex League before again being shut down and missing the rest of the season. He again missed the entire 2025 season so since being drafted Miles has only played 14.2 innings in 3.5 years. Miles had big stuff in college at Missouri but struggled to get outs. In his few professional innings he’s shown the ability to get strikeouts with an above 30% strikeout rate in both seasons and some ability to throw strikes but he just hasn’t pitched. He showed a fastball in the upper 90s during his 2024 season and a slider with good depth but not sure what the rest of his arsenal is and might be one of the most interesting prospects in the AFL this year. 

Ryan Murphy RHP: Drafted back in the 5th round of the 2020 draft Murphy has been in the Giants organization for awhile. Out of his 5 professional seasons he’s struggled with injuries that shortened his 2022, 2024, and 2025 seasons but he was able to throw 107.1 innings in both 2021 and 2023. Murphy has not just struggled to stay on the field but he’s struggled in general meaning he hasn’t made it above AA where he’s been stuck since making his AA debut in 2022. He broke onto the scene in 2021 with a 2.52 ERA while striking out 39.3% to a 6.2% walk rate and jumping onto prospect boards. Since then his strikeout rate has slowly dropped especially since getting into AA where it’s never been above 25.6% and his walk rate has been inconsistent. Murphy has shown very average stuff with very average velocity. I would guess the Giants are going to make a decision on him either this offseason or next year. 

Jose T. Perez RHP: Another very weird case like Miles Perez was signed in the International Class of 2021 and threw 3.1 innings in the Dominican Summer League before getting injured. With nothing I could find in Perez has not pitched a single game in the Giants organization since then. He made his return this season jumping from the DSL after a 3 innings start to the Complex League where he threw 21.2 innings to a 4.57 ERA and 5.37 FIP. He made 2 appearances for 2.1 innings in Low-A as well to a 15.43 ERA after giving 4 runs in his first outing but having a clean second one. This is very weird because there’s basically nothing on Perez. I can’t find why he was injured/missed 3 full years or what his pitches were. I’ll add to this after his first AFL outing is available because I have nothing on him. 

Juan Sanchez LHP: Signed out of Venezuela in 2017 Sanchez has been in the Giants organization for a long time. He’s slowly climbed the ranks, basically being promoted to each level every season and pitching out of the bullpen in AAA in 2024. He likely had Tommy John surgery and has been out the entire 2025 season but looked great in 2024 with 34.1 innings to a 3.93 ERA but struggled with walks with a 18.8% rate. Before the injury he threw both a sinker and four seam fastball that sat in the low 90s topping out at 96 mph. His best pitch and the one Sanchez used most often was his changeup that sat in the mid 80s and has some great late action which made it have a 39.6% whiff rate in AAA during the 2024 season. He also has a mid 80s slider which is his worst pitch. He’ll likely settle in as a mid inning lefty specialist if anything but what he is after the injury has yet to be seen. 

Maui Ahuna SS: The 2023 4th round pick didn’t get off to a great start. His last season at Tennessee he tried to play through a back injury and his stats dipped because of it. He continued to deal with injuries in 2024 only playing 23 non rehab games in Low-A to a bad result and having to get Tommy John surgery in the middle of the year. Ahuna came back this season to Low-A in late May after some rehab games to start the season and he hit pretty good .266/.375/.427 for a 124 wRC+. He kept his usual walk rate at 11.3% and his strikeout rate stayed a career same at 25%. He earned a promotion to High-A but only played in 11 games when he hit the injured list in early August and didn’t come back this season. In those 11 games he played well hitting .311/.404/.467 for a 142 wRC+. Ahuna has about average raw power from the left handed side and tries to pull most pitches with a long swing. He also struggles with contact because of that long swing only making contact on 68.2% of pitches this season. Ahuna tends to roll over on fastballs and whiff on breaking pitches leading to his higher than normal strikeout rate. He’s mostly known for his glove though. Despite the numerous injuries Ahuna has always looked great at short with great hands and an athletic frame. He has the speed and athleticism to steal more bases but has never been very aggressive, only stealing 12 bases in 63 games this year.

Parks Harber UTL: Acquired at this year’s deadline along with three other prospects from the Yankees for Camilo Doval, Harber has been very good at the plate since joining the Giants High-A team. Harber has played 25 games in the Giants organization and hit .333/.454/.644 for a 195 wRC+. He hit the same number of homers (7) in those 25 games than he has with the Yankees in 77 games the last two seasons. The Yankees signed Harber after he went undrafted in the 2024 draft even after putting up a 1.073 OPS in his last season at North Carolina with 20 homers. He’s just continued to hit after he was signed last year he hit for a 141 wRC+ in 23 games by the end of the season. This year he dealt with an injury in mid June missing almost two months and only played 79 total games. In combined games between the Yankees Low-A and High-A as well as the Giants High-A Harber hit .323/.420/.550 for a 173 wRC+. He has an eye for the zone walking 12.8% of the time while swinging at a below average rate. He doesn’t make elite contact right now but makes enough in the zone to keep excelling in the minors. The Yankees had been playing him at first base and third base but the Giants changed it up. They kept him playing primarily third but had him play some innings in both corner outfield spots. Harber is alright at third, likely below average so it's great he’ll likely now be able to play first and two outfield spots to just keep his bat in the lineup as much as possible.

Walker Martin 3B/SS: The Giants drafted Martin out of high school in the 2nd round of the 2023 draft but he’s really struggled in pro ball so far. His first season in 2024 started late due to a back injury and he really struggled when playing. He showed enough plate discipline and power to hit above average in 44 Complex League games hitting .229/.413/.382 for a 113 wRC+ but his red flags were loud with a 37.6% strikeout rate and only a 48.5% contact rate. He was promoted to Low-A and played in the last 25 games of the season and his problems got even worse when he hit .202/.358/.333 for a 95 wRC+ and struckout 46.3% of the time. This season he played 108 games back in Low-A and was about the same, maybe a bit better, hitting .234/.353/.384 for a 107 wRC+. He cut down on his strikeouts and made more contact at a 66.6% clip which is still heavily below average. He showed his potential at times with a 7 game stretch where he hit .357 with 6 home runs but in total he struggled. Martin also didn’t show off his speed which was said to be above average only stealing 13 bases. He’s also really struggled in the field. In 2024 he had 29 errors in only 69 games at shortstop which caused the Giants to have him split time between short and third where he had 23 errors in 91 games so a bit better. He might profile as a second baseman but he won’t play unless the bat clicks more.

Thank you for reading for shorter breakdowns check out my Twitter @drew-durstock. Each day I'll release a new team's prospect breakdown.