The 2024 Arizona Fall League starts today. Here’s what you need to know about the Mesa Solar Sox.
The Mesa Solar Sox of the Arizona Fall League take the field tonight at 6:30 Mountain Standard Time at Sloan Park, the Spring Training home of the Chicago Cubs. There are eight Cubs minor leaguers on the Solar Sox roster, along with players from the Athletics, Red Sox, Rays and Angels.
The Arizona Fall League was designed as a kind of “finishing school” where prospects who needed extra work at the end of the season could get some more work in. It also serves as a place for MLB teams to get one last look at minor leaguers before decisions have to be made on the 40-man roster and trades at the Winter Meetings.
Players like the Arizona Fall League because they get another chance to play and impress their front office. But the one thing that players always rave about is the chance to meet with and play with players and coaches from other organizations.
In recent years, however, teams have become increasingly reluctant to have their better pitching prospects play in the AFL. It’s simply a matter of limiting innings, keeping pitchers healthy and away from the thin air and small ballparks of Arizona. Usually the only top pitchers there are ones who missed extensive time and are coming back from an injury. So the AFL has become a supercharged offensive league. Keep that in mind if you see players hitting .420 with six home runs or something similar. Expect a lot of games where both teams score double-digit runs.
The biggest name from the Cubs on this year’s Mesa Solar Sox roster is catcher Moises Ballesteros. Ballesteros is arguably the best hitter in the Cubs system and doesn’t really need to hit off of second-rate minor league pitching. But Ballesteros is here to get more experience behind the plate. The Cubs are committed to making Ballesteros a catcher, so getting experience with non-Cubs coaches and catching non-Cubs pitchers will be a good experience for him.
First baseman Jonathon Long had a breakout performance in Double-A Tennessee this past season. After getting a mid-season promotion from South Bend, Long hit .340/.455/.528 with seven home runs in just 46 games. Long is here to prove that breakout wasn’t a fluke. Long also played third base and left field as well as first, so I would expect that the Cubs would like to see him work on his defense at those two positions for Mesa.
The other Cubs position player on the Solar Sox is infielder Ben Cowles. The Cubs got Cowles from the Yankees in the Mark Leiter Jr. trade, but he was dealing with a broken hand when the trade was made, so he has only played seven games (regular season and postseason). Thus he’s making up for lost time. He’s a decent prospect who can play three infield positions and has some utility infielder upside.
I hope I didn’t talk down the four Cubs pitchers on the Solar Sox, because while none of them are top prospects, they aren’t just roster filler either. Maybe the most promising of them is right-hander Luis Rujano, a 21-year-old who was the Cubs’ 13th-round pick out of high school in Florida in 2022. Rujano has pitched for the Low-A Myrtle Beach Pelicans for the past two seasons and he has a big, mid-90s fastball and a hard-breaking slider that can be deadly when he can control it. Rujano has both started and relieved, but his long-term future is the bullpen. If he can learn to throw his slider for a strike consistently, he could have a major-league future.
Another interesting arm is Grant Kipp, whom the Cubs signed as an undrafted free agent out of Yale in 2022. Kipp is a pitcher with a kitchen-sink full of offspeed and breaking pitches who has put up some impressive strikeout numbers as a starting pitcher in South Bend. However, he missed the first half of the season with injury, so he’s in Arizona to get some more innings in.
The Cubs signed Vince Reilly as a minor-league free agent after the Athletics released him at the end of the 2023 season. Reilly had a strong season in 2024 for Low-A Myrtle Beach as a reliever. He features a mid-90s fastball and a hard slider. He’s a pure reliever, but there’s some potential there. He’s a bit short (5’10”), which may be why he’s been underrated.
Shane Marshall was the Cubs’ 14th-round pick in 2022. He missed all of the 2023 season with Tommy John surgery, but he returned this year and worked as a closer for Myrtle Beach this past year. The thing to know about Marshall is that he’s a converted catcher who only pitched 1⅔ innings in college at Georgia. So he’s raw and needs experience. Currently Marshall has a mid-90s fastball and a hard slider, but the Cubs believe that there is more there with more experience. Calling Marshall raw but promising is an understatement. He’s clearly in Mesa to gain more experience on the mound.
Sam Thoresen is also listed on the Solar Sox roster, and I’m going to assume he’s one of the “Taxi Squad” players who will only pitch once or twice unless there’s an injury or some other pitcher drops out. Thoreson’s a pure reliever who walks too many batters. With a name like “Thoresen,” it won’t surprise you that he’s a Minnesota native whom the Cubs signed as a undrafted free agent out of the University of Minnesota in 2020. He’s pitched well enough to keep around and the Cubs are letting him get more experience in Mesa.
As good as Ballesteros is, he’s only the second-best prospect on the Solar Sox this year. The honor of the highest-ranked prospect goes to Rays first baseman Xavier Isaac, who had 18 home runs, 21 doubles and 15 steals as a 20-year-old in High-A and Double-A for the Rays. Isaac is likely to be the Rays’ first baseman of the future.
The Rays are also sending slick-fielding Tre’ Morgan, who also has a strong hit tool, evidenced by the .371 batting average that he posted in High-A Bowling Green this past season. The left-handed-throwing Morgan has mostly been a first baseman in the Rays system, but the Rays want to move him to left field. So he’s in the AFL to learn a new position as well.
Some AFL games will be streamed for free on MLB dot com, but which games get broadcast is kind of a crapshoot. Just check the official MLB site or the AFL site each day to see if the Solar Sox are being broadcast. The All-Star Game and Championship Game are on the MLB Network every year.
We’ll have regular Monday updates on the Cubs playing for the Solar Sox throughout the entire six-week season.