2025 was a year of improvement for the Chicago White Sox. Depending on how the last week of the regular season goes, we could see the South Siders have an improvement of over 20 games from where the organization was in 2024.
Some of that improvement can be credited to the coaching staff. Some of it is, of course, because of the young rookies who have made their mark this season. But there’s also the White Sox veterans who took an unexpected step forward during the 2025 season. The guys who worked hard over the offseason and improved their game tremendously.
As I go through every mainstream MLB award and apply it to the 2025 Chicago White Sox, narrowing it down to just one name for Most Improved Player proved to be difficult.
Contenders for Most Improved Player
Miguel Vargas and his April swing change have been heavily discussed throughout the 2025 season. The fact of the matter is that Vargas was too overmatched to play at the big league level in 2024 and he transformed himself into a quality everyday player in 2025, even though his 97 OPS + is still slightly below league average.
Jordan Leasure was another player that came to mind. Leasure had a 6.52 ERA in 2024 and spent a lot of the season in Triple-A. This year, he rebounded with a 3.45 ERA in 66 appearances. He leads the White Sox in saves (7) and raised his K/9 from 7.5 to 11.1.
Colson Montgomery also deserves some consideration, of course. A down year in the minor leagues in 2024 and a horrific start to the 2025 season had a lot of people giving up on Colson before he even made his Major League debut.
19 home runs in the second half of the season have restored faith in Montgomery‘s ability to be a marquee player at shortstop for the White Sox. The improvement has been out of this world, but I’m not sure it’s in the spirit of the award to give it to a rookie.
White Sox Most Improved Player - Lenyn Sosa
Runner-up: Miguel Vargas
The player most deserving of the White Sox team award for Most Improved Player is infielder Lenyn Sosa. Sosa has a career-high in every single offensive category in 2025. He is the White Sox team leader in hits (131), home runs (21), and RBIs (72).
The main reason I consider Sosa to be the Most Improved Player on the team is because, unlike Vargas, he became a player I never knew he was capable of being.
Vargas has a .709 OPS and 15 home runs this season. That’s all good and well, but he was a former top prospect in all of baseball that was the headlining return of a trade with the Dodgers. He’s supposed to at least be an average MLB player. He might have lowered the bar for himself significantly in 2024, but in a vacuum, Vargas' 2025 numbers don’t exceed the expectations I had for him when the White Sox made that trade.
Sosa, on the other hand, continues to prove me wrong. Even after he started the 2025 season pretty strong, I wrote about how Sosa is someone the White Sox needed to trade as soon as possible. I saw him as more of a backup infielder than an everyday player.
Given his defensive struggles and occasional lack of awareness, the middle infield didn’t feel like a long-term home for Sosa. Hitting 10 Home runs in a season was not good enough to make up for those flaws. Hitting 20-25 home runs is a different story.
With 21 home runs in 72 RBIs on the season, Sosa has turned himself into a legitimate threat at the plate. There’s value in that, especially for a 25-year-old that should only continue to get better. The improvement for Sosa this season has him firmly in the mix to get regular at-bats on the 2026 White Sox. He could even be a go-to guy on the next contending team.
In my opinion, Lenyn Sosa is without question the Most Improved Player on the 2025 Chicago White Sox.