The Angels selected Reid Detmers with their first round pick in the draft, but was he the right selection? Let’s look at the data.
Many fans are hoping that Reid Detmers is the savior of the Angels’ rotation in the near future given his polish. However, is he all polish with limited upside? It seems that way as of right now. Detmers is the type of prospect that isn’t high-variance, but he isn’t one that has a particularly high ceiling.
Los Angeles’ first pick in the 2020 draft was far from a pick positively-viewed by the analytics crowd. A left-handed pitcher out of Louisville, Detmers’ average fastball velocity was 90.6 mph in 2020, with well below-average spin (2156 rpm), a short extension (5.64 feet), high release height (6.07) which makes it hard to pitch up. He’s got near perfect spin efficiency (usually above 98%) but it’s rather useless as the velocity and lack of release height make the pitch suboptimal at the top of zone (as evident by the -4.5 vertical approach angle).
Now, in college baseball he’ll get swings and misses because he locates it somewhat well, but swing-and-miss rates in college baseball don’t translate at all. Pitch metrics are far more predictive of future success and when you’re sitting 89-91 w/ average movement, you’ll have to live down, leading to volatile statistics as the lower a pitcher works in the zone. The lower the odds of a swing-and-miss, the more likely you are too give up ground balls and inflated exit velocities relative to the release speed going in.
Detmers’ changeup might’ve been his best pitch metrically, or at least close to it. It had plus horizontal break in 2020 with some tumble, though he only threw it for a strike 33% of the time. Changeups tend to be hard to evaluate just purely off the data as feel for the pitch tends to outweigh the metrics due to its inability to be effective when it’s not thrown for a strike at an average rate at least.