LA Angels: An analytical look at 2020 first-rounder Reid Detmers

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.

Curveball and Outlook

Detmers’ best pitch out of college was his curveball, a somewhat good-looking pitch visually, it’s just not as good as some said it was. Curveballs at 72.63 mph, what he averaged at Louisville, don’t fare well even with double-digit vertical drop and some horizontal break. It’s still an above average pitch because of its axis and similarities towards the fastball out of hand (similar release height at 6.01) and its steep approach angle. His curveball got 11 swing-and-misses on 110 pitches in 2020, which is well below average, but he also threw it for a strike 69% of the time, which is extremely valuable as curveballs have the lowest strike percentage among pitch types generally. It’s a good, not great pitch, but velocity is the end all be all in baseball now and with such low velo, the room for error is much higher.

Now, Detmers wasn’t a bad pick for the Angels, but the upside you’re getting is severely limited and at best, the Angels are looking at a number four starter in a staff that has plenty of those types. Given the Angels’ horrific track record with developing arms, maybe Mick Abel wouldn’t have been a strategic pick here, but his data is far better, and he likely would’ve saved them some money for a shot at Cole Wilcox in the third round over David Calabrese. In that case, they would’ve had a better pitcher then Reid Detmers (in Wilcox), more upside in Abel, and could’ve used their fourth round pick on somebody far less volatile. Instead we’re left with two extremely raw prep bats, a low ceiling starter with below-average velocity and only two above-average pitches, and a late round flyer in Adam Seminaris.

Let’s hope that Detmers winds up being a good pick despite the poor metric data. The Angels need it.