Pittsburgh Pirates: Unluckiest Pitches of the 2023 Season

Mitch Keller’s Sinker - wOBA: .309, xwOBA: .293

Mitch Keller added a sinker to his arsenal last year. The pitch was arguably his saving grace in 2022, and it continued to be an effective offering in 2023. However, even though it was a reliable pitch in Keller’s arsenal, it could have been even better.

Keller’s sinker held batters to just a .258 batting average, but .346 wOBA, and .309 wOBA. When opponents made contact with the pitch, they had just a 86.7 MPH exit velocity against it, well below the league average rate. But a deeper dive shows just how good this pitch can be. While his xSLG percentage with his sinker was still roughly the same at .342, his xBA drops to .236. Meanwhile, his expected wOBA sinks below .300, down to just .287 (no pun intended). 

We already looked at what a wOBA around the .300 looks like with Falter’s fastball, but what would a wOBA well below that look like? Well, it would look like Yuli Gurriel, Yasmani Grandal, or Isiah-Kiner Falefa in 2023. Their wRC+ ranged from 77 to 82. FanGraphs describes a wOBA of .290 or lower as “awful” while .300-.310 is between poor and below average.