Yankees’ Masahiro Tanaka finally discovers Opening Day formula

Aaron Boone said the decision was simple after he knew Luis Severino’s rotator cuff inflammation would sideline him to begin the season. The manager called Masahiro Tanaka the “obvious choice” to start Opening Day in Severino’s place, despite Tanaka’s muddled history in three previous outings to start the season. Tanaka entered Thursday having allowed 13…