player (ja:育成選手制度 (日本プロ野球)). On April 23, 2021, Shackelford signed a contract with the BayStars as a registered player under management. (Ja:支配下選手登録) On April...

The Developmental Player System (育成選手制度, Ikusei Sensyu Seido) is a system that allows players to be held for the purpose of training players separately...