Early results on YoY pitcher velocity

[Bertz]

One of the quickest things to matter in a new season is going to be YoY velocity changes.  This is stupid early, but here's every pitcher on the team that's thrown so far.

Pitcher - '23 velo / '22 velo

Stroman - 91.7 / 92.9

Steele - 92.3 / 92.4

Taillon - 94.3 / 94.1

Assad - 94.3 / 93.0

Fulmer - 95.1 / 94.3

Thompson - 93.4 / 93.8

Leiter - 90.9 / 91.2

Boxberger - 93.0 / 92.8

Alzolay - 96.8 / 95.0

Merryweather - 96.4 / 97.4

Rucker - 95.5 / 94.9

Alzolay is the clearest positive.  If he's going to be sitting 97 permanently he will be the permanent closer within a few weeks.  Assad too, though his coming out party already happened in the WBC.  One other I'll note though is Steele, his velo being flat while pitching in those conditions might mean he's really added some juice to his fastball.

Stroman and Merryweather are the only guys down noticeably.  I don't love Stroman being down, because he got warmed up for the WBC I wouldn't expect him to e.g. be going through dead-arm.  Merryweather hopefully it was a one-off, because if he's not throwing absolute gas he shouldn't be long for the roster.

[Brock Beauchamp]

I wanted to split this out into its own thread because it's something worth tracking as the weather warms. Given the constant race for velocity in baseball over the past 15-ish years, I'm interested to see if pitchers wear down a little more quickly this year and possibly lose a tick of velocity due to the much faster pace forced by the pitch clock.

I'm skeptical this will happen but it'd be good for the sport if pitchers lost a mph or two over a season.

[Hairyducked Idiot]

I seem to recall velocity has some distinct month-to-month patterns over the course of a season, but I don't remember what they are.

[Bertz]

1 hour ago, Hairyducked Idiot said:

I seem to recall velocity has some distinct month-to-month patterns over the course of a season, but I don't remember what they are.

Historically, velo has moved with the weather.  Starting low in April and peaking in August.  Around 1.5-2 MPH on average.  Some of this is the weather itself (i.e. guys can throw harder when it's warmer and they're looser), some of it the nature of guys ramping up from the offseason.

I haven't seen any studies focusing on the last few years, but anecdotally it seems to vary much less over the course of each year.  My read on why is that guys have now trained enough to throw at essentially 100% right away on February 15th.  So a few years ago I'd look at all those guys who were flat and be all "if they're flat now then by June they'll be up quite a bit!" but I'm less confident than ever of that being inevitable.  It still happens, Drew Smyly is a great case last year (91.9 in April, 93.3 in August), but it's no longer the universal truth it used to be.

[Bertz]

There's some data cleaning that happens overnight and might shift these numbers, but as of right now looks like Wesneski is up 1.3 MPH, from 93.4 -> 94.7