As Gunnar Henderson stepped to the plate in the bottom of the ninth inning of Game 2 of the AL Wild Card Series on Wednesday night, his team down by a run and one out from elimination, it felt like something special was brewing. Late-inning tension, high stakes, one of the sport’s biggest stars: The postseason was peaking, and the young superstar held the Orioles’ fate in his hands, poised to deliver a signature moment. Unfortunately, he had to deal with Lucas Erceg’s changeup.
Lucas Erceg, Filthy 91mph Changeup. ? Royals Advance. ? pic.twitter.com/kWKQQy0gzZ
I’ve followed Erceg all year, first from afar, mystified by the flamethrower that materialized out of nowhere in the Oakland bullpen, and then with a closer eye when he moved to Kansas City, watching him slip seamlessly into the fireman role in the Royals bullpen. His eye-popping fastball velocity caught my attention, but it’s the changeup stealing the show on the bright October stage.
Lucas Erceg Pitch Specs
| Pitch Type | Induced Vertical Break (in.) | Horizontal Break (in.) | Release Height (ft.) | Velocity (mph) | Usage (%) |
|---|---|---|---|---|---|
| Changeup | 6.7 | -17.9 | 5.9 | 91 | 19.9 |
| Four-seamer | 15.1 | -10.1 | 6 | 98.6 | 30.9 |
| Sinker | 10.2 | -15.8 | 6.1 | 98.5 | 21.3 |
| Slider | -3.1 | -0.1 | 6 | 85.7 | 27.9 |
As the table shows, Erceg’s velocity sits at the top of the scale. His four-seam fastball averages 99 mph. Again, he sits at 99 mph. But the results on it were just so-so: It graded out at 0.1 runs per 100 pitches by Baseball Savant’s run value calculations, neither helping nor really hurting him. I think the pitch’s performance can be explained by its exceedingly “normal” shape.
(Shout out to Leo Morgenstern.) Erceg throws his fastball from a 43-degree arm angle, which is smack dab in the tall part of the histogram among major league pitchers. From that bog-standard arm angle, his fastball gets roughly league-average induced vertical break. Max Bay’s “dynamic dead zone” application projects how batters might perceive Erceg’s fastball relative to arm angle expectations. While the pitch drifts further to his arm-side than batters might initially expect, the vertical expectations are basically identical. The conventional shape of his four-seam fastball knocks it down a peg from a “stuff” perspective, taking it from plus-plus to maybe just plus. But a high-velocity fastball doesn’t exist in a vacuum — it exists in the context of all in which it lives and what came before it.
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