10. San Diego Padres
Gavin Sheets
I remember when I found out that Sheets was signing with the Padres on a Minor League contract. It was an afterthought move at the time, but the Padres liked what they had seen from Sheets with the White Sox and thought there was untapped potential.
Boy, was there ever.
In 132 games this season, Sheets is hitting .263/.326/.456 with a .782 OPS, 19 home runs and 64 RBI. He’s far exceeded expectations and has helped the Padres both in left field and as a designated hitter. He’s another one of AJ Preller’s big scouting wins.
-Robert Murray, FanSided MLB Insider
9. Boston Red Sox
Aroldis Chapman
It isn’t too often that you see a 37-year-old on this list, but how can the Boston Red Sox’s Most Improved Player be anyone else? I mean, Chapman wasn’t awful for the Pittsburgh Pirates last season, but it certainly appeared questionable for the Red Sox to sign him to be their closer, especially considering his history at Fenway Park with the New York Yankees.
Well, Chapman has silenced all of the doubters emphatically by putting together one of the best seasons a Red Sox reliever has ever had. I don’t think I’m being overdramatic here: Chapman’s ERA is just a shade above 1.00, and he recently had a two-month stretch in which he didn’t allow a single hit. He’s been that dominant. Oh yeah, the walks are way down, too. I guess purposefully locating your pitches does matter.
The Red Sox are where they are because of Chapman, and if they go on a deep postseason run, Chapman will be right in the middle of it.
-Rotman
8. Seattle Mariners
Cal Raleigh
Sometimes the obvious pick is the right pick. And in the case of Cal Raleigh, we’re talking about a 62-point wOBA increase that puts him among the five most improved hitters year-over-year from 2024.
It comes down to how Raleigh has become a switch-hitter who is actually good at, well, switch-hitting. Prior to this season, he had a .681 OPS and 20 home runs as a right-handed batter. With a couple weeks still to go in 2025, he has a 1.005 OPS and 20 homers as a righty batter this season. And it can’t be said loudly or often enough that he’s doing this at possibly the worst hitters’ park in the Majors.
Granted, Raleigh has regressed defensively after posting 17 Defensive Runs Saved and winning the Platinum Glove last year. But if anything is worth such regression, it’s a 50-homer and possibly MVP-winning season.
-Zachary Rymer, SoDo Mojo
7. New York Yankees
Trent Grisham
Grisham was a non-tender candidate after he played only sparingly for the New York Yankees in the 2024 season. He’s always been a solid defender and has always had some power, but he’s become a crucial bat at the top of their order this year seemingly out of nowhere.
Grisham got off to a hot start, but it was easy to assume he’d cool down imminently considering his career-long track record. Well, he has hit 30 home runs thus far, an astonishing feat considering his previous career high was 17 back in 2022, and he’s shown no signs of slowing down. For those who say the short porch has helped him, Grisham’s numbers away from Yankee Stadium are far better. This is simply a good ball player who is going to make a lot of money this coming offseason as a free agent.
-Rotman
6. Detroit Tigers
Dillon Dingler
Dingler was hardly on anybody’s radar at the start of the year; a non-prospect, his first taste of MLB pitching ended with a miserable .505 OPS last season. Flash forward a few months, though, and Dingler has become Detroit’s No. 1 catcher with a bullet, slashing .282/.331/.438 with excellent defense behind the plate.
Even more encouraging, there’s nothing about it that suggests it’s not sustainable: Dingler has cut his strikeout rate drastically, and very few catchers combine this sort of contact ability with an optimized swing that’s resulted in a .491 expected slugging percentage. He’s pulling the ball in the air much, much more without any regression in his contact metrics, and that’s a huge development.
-Landers