Photo by Allan Dranberg/Icon Sportswire

Stat of the Week: The Most Improved Player in MLB

By Mark Simon

Cardinals right fielder Jordan Walker posted a -1.7 bWAR last season.

That's a really bad season. There were 26 position players with a -1 bWAR in 2025. The -1 bWAR players fall into two categories: the young ones struggling to survive and the veterans who are about to retire or be released. Besides Walker, only four of those 26 players have even played in the majors this season.

Walker hasn't just played. He's gone from struggling youngster to one of the best players in baseball pretty quickly.

In our opinion he's the most improved player in the sport through the first two months of the season. He’s living up to the high expectations that came with being one of MLB’s top prospects a few years ago.

Walker's -1.7 bWAR in 2025 was tied for the worst among all position players. He's currently at 3.0 to start 2026, which ranks third behind Bobby Witt Jr. and Andy Pages (3.3).

Walker changed his batting stance over the last two years to make it much more closed. He's found something he's comfortable with now. As a hitter, Walker has performed above average against every type of pitch this season. His bat speed ranks second in MLB. He's hitting .301 with 13 home runs and a .955 OPS.

Jordan Walker - 2026 Season

Category

Stat

NL Rank

OPS

.955

3rd

HR

13

T-3rd

Adjusted OPS+

173

1st

We tend to focus on defense, and the improvements to Walker's game are significant here too. Walker's 7 Runs Saved in right field trail only Wilyer Abreu among right fielders, and he has almost as many Good Fielding Plays as he made all last season.

Jordan Walker - 2026 Season

Category

2025

2026

Defensive Runs Saved

-11

7

Good Fielding Plays

10

9

Defensive Misplays & Errors

14

4

Walker has been a completely different defensive player, making catches like this one and throws like this one. He's harnessed his 99th percentile arm strength (top 10% of throws average 96 MPH) to cut runners down. He already has as many assists without the use of a relay man as he did in the last two seasons combined (3).

The Cardinals rank third as a team in Defensive Runs Saved this season. They're 11th in how often they turn a ball hit in the air in the outfield into an out compared to 26th last season.

There's still some work for Walker on the defensive side. Runners are advancing an extra base on hits against him at the second-highest rate of any right fielder even with the throw-outs. But it seems like having a little patience with him will have a nice payout.

The FieldingBible.com website is a great resource for your defensive stat needs.

  • Player and Team stats

  • Defensive Runs Saved leaderboards

  • Much more!

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