Which Guardians’ Prospect Should Be Called Up Next?

Going under the hood on Baseball Savant

The gulf between the majors and Triple-A performances continues to widen - what stats can help us determine which Guardians’ hitters are ready for the bright lights of the big leagues?

Folks, I have a confession to make. Until today, I was unaware that I could search performances against pitch-types and pitch-velocities on Baseball Savant, and now that I know this, I am ready to offer some more nuance in discussions on which prospects need called up, aside from what my eyes and a box score/FanGraphs page can tell us.

For example, I can now tell you the whiff rate and expected weighted on-base average against fastballs 95 mph and greater of five Guardians’ hitting prospects that we’ve probably all wondered about this season:

Chase DeLauter - .452 xwOBA, 28.6% whiff rate
Juan Brito - .444 xwOBA, 33.3% whiff rate
Brayan Rocchio - .355 xwOBA, 16.7% whiff rate
Petey Halpin - .278 xwOBA, 42% whiff rate
CJ Kayfus - .132 xwOBA, 41.2% whiff rate

As a comparison, the leaders on the Guardians against 95+ mph fastballs are Daniel Schneemann at .646 wOBA(!!!), Bo Naylor at .490 wOBA, Jose Ramirez at .353 wOBA, and Steven Kwan at .344 wOBA.

I can also tell you the whiff rate and expected weighted on-base average of these same five hitters vs. changeups:

Brito - .416 xwOBA, 18.2% whiff rate
Halpin - .403 xwOBA, 19.7% whiff rate
DeLauter - .361 xwOBA .361, 54.5% whiff rate
Rocchio - .345 xwOBA .345, 20% whiff rate
Kayfus - .310 xwOBA, 30.5% whiff rate

For comparison, the Guardians’ leaders are Manzardo at .392 wOBA, Ramirez at .347 wOBA, and Gabriel Arias at .307 wOBA.

And against breaking balls:

DeLauter - xwOBA .271, 23.5% whiff rate
Kayfus - xwOBA .253, 42.2% whiff rate
Halpin - xwOBA .248, 30% whiff rate
Brito - xwOBA .243, 38.2% whiff rate
Rocchio - xwOBA .215, 34.1% whiff rate

And the Guardians’ standouts here are Ramirez at .355 wOBA, Jones at .343 wOBA, Santana at .339 wOBA, Kwan at .313 wOBA, Schneemann at .299 wOBA, Manzardo at .288 wOBA.

A helpful caveat is that the sample sizes for these players is still small, so there will be variance in the future. It is also important to note that pulling fly balls helps players beat their xwOBA and DeLauter, Brito and (to a somewhat lesser extent) Halpin have proven abilities there. I have chosen xwOBA rather than wOBA for the prospects in hopes of showing a little more of the potential that is hard to contextualize with the noise of minor league hitting environments.

For me, I think I can see the logic in letting DeLauter see a few more breaking balls and show what he can do, but, generally, he looks ready for a promotion to me considering the Guardians’ lack of right field hitting in general. If DeLauter has a growth mindset and a strong mentality, he has the tools to continue development while contributing in the big leagues. When Brito is healthy again, I hope he gets a call up because handling fastballs and changeups as well as he does combined with good plate discipline and pulled-fly-ball abilities should help mitigate some questions on his knack of handling breaking balls. Halpin makes sense to me as a September call-up, but I don’t think we should be buying in on the Kayfus and Rocchio hype quite yet.