Wearing some kind of support on his throwing hand to protect his thumb. Something like this:
healthproductsforyouBuy Push Sports Thumb Brace of BRACELAB. On Sale Thumb and Finger Supports, Upper Limb Orthotics, Orthopedics products. Push Sports Thumb Brace stabilizes the middle thumb joint (MP joint) with an adjustable strap system, while minimizing coverage of the palm to optimize hand function during sp...
https://www.healthproductsforyou.com/p-push-sports-thumb-brace.html[https://www.healthproductsforyou.com/p-push-sports-thumb-brace.html?gclid=EAIaIQobChMIqK_Er-rj5QIVrR-tBh2K8wc5EAQYAyABEgKtA_D_BwE]
Apparently he wanted to play and could have but wasn't needed.