SF Giants top prospects: No. 15 — RHP Kai-Wei Teng
Age: 21
Highest Level: Class-A (Augusta)
Acquired: Trade (2019)
Future-Value Grade: 40+
When the Giants traded Sam Dyson to the Twins at the 2019 trade deadline, Teng was packaged alongside Jaylin Davis and Prelander Berroa. Teng saw an uptick in production as soon as he joined the new organization.
With Minnesota’s Single-A affiliate, Teng threw 50.2 innings and posted an impressive 1.60 ERA. However, after joining the Giants at the same level for his final five starts of the season, Teng produced a 1.55 ERA, saw a spike in his strikeout rate (8.7 to 12.1 K/9), and a dip in his walk rate (2.5 to 2.2 BB/9).
Just 21 years old, Teng doesn’t have the projection left typical of someone his age. He’s already 6’4” and 260 pounds and has pretty much maxed out his frame. He has very smooth mechanics and a good feel for a slider, changeup, and curveball. He works off a low arm-slot that probably will prevent his fastball from ever topping the low-90s. None of his pitches project as plus, but all have the potential to be 50-grade pitches.
Pitchability prospects tend to perform really well in the lower minor leagues, but then stall as they progress. Guys like Clayton Blackburn and Edwin Escobar both come to mind. Teng comes with similar caveats, but his secondary pitches are more advanced than both Escobar and Blackburn at this point.
If it all comes together, Teng could be a solid innings eater. Most likely, he falls somewhere from a swingman role to a back-of-the-rotation arm. Assuming he can maintain his frame and pitchability over the break, he’s a pretty good candidate to move quickly through the system.
He was particularly dominant last year, so we may be underselling what he’s capable of. However, it’s hard to foresee his stuff taking another step as is. When he does get back to affiliate ball, Teng could be a prime candidate to move quickly up the system.