It might seem easy to envy the life of a major league baseball player: even the least famous of them make a lot of money, have a bunch of Twitter followers, and get to play a game for a living. But it’s always been a little tougher for me to envy the life of a relief pitcher, who seems to experience the worst drawbacks of the job with little of the upside. As opposed to starting pitching — where one’s mistakes can be more easily made up for by logging good innings — relief pitching is simply less forgiving, with every mistake massively amplified. And no pitcher has embodied that more in the past two seasons than Evan Scribner.
You might know about Scribner, as he was just traded from the A’s to the Mariners last month. There’s more than that to him, of course, and one of the big things is the number of strikeouts he’s recorded compared to the number of walks he’s issued. That’s important, because we like the K-BB% stat a lot for pitchers: it’s been shown to be the best ultra-simple ERA estimator we currently have. It’s not perfect, but it can be a handy way to get an idea of how a pitcher could perform in the future. There’s even some work that shows it performed better than xFIP, FIP, and SIERA at predicting second-half ERA after a first half was in the books. All of this is just a set up, really, for this table, which shows the 15 best K-BB% marks for relievers with at least 70 innings pitched between 2014-2015:

Top 15 Relievers by K-BB%, 2014-15, min. 70 IP
Aroldis Chapman |
46.3% |
11.9% |
34.4% |
1.80 |
Andrew Miller |
41.6% |
7.6% |
34.0% |
1.96 |
Kenley Jansen |
38.7% |
5.8% |
32.9% |
2.60 |
Sean Doolittle |
35.5% |
4.4% |
31.1% |
2.95 |
Dellin Betances |
39.5% |
9.5% |
30.0% |
1.45 |
David Robertson |
35.8% |
7.1% |
28.7% |
3.24 |
Craig Kimbrel |
37.7% |
9.9% |
27.7% |
2.08 |
Wade Davis |
35.3% |
8.1% |
27.2% |
0.97 |
Jake McGee |
32.8% |
5.7% |
27.1% |
2.07 |
Koji Uehara |
31.1% |
4.2% |
26.9% |
2.41 |
Evan Scribner |
26.3% |
1.4% |
24.9% |
4.40 |
Ken Giles |
32.5% |
7.8% |
24.8% |
1.56 |
Carson Smith |
32.6% |
8.0% |
24.6% |
2.07 |
Cody Allen |
33.6% |
9.0% |
24.6% |
2.53 |
Brad Boxberger |
34.4% |
10.0% |
24.3% |
3.03 |
The list is pretty much a who’s who of dominant relievers, as every guy in the top 10 is closing or has closed for their respective teams sometime during the past two years. Then there’s Scribner, who sticks out like a sore thumb mostly because of his ERA and the fact that he walks no one. Well, not no one, but in major league terms, he walks no one. He has the lowest walk rate among relievers who have pitched meaningful innings in the past two years (20+ innings), and it’s not particularly close; in raw numbers, he’s walked four batters in 71.2 innings.
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