Tuck had been working with Sox catcher Ryan Lavarnway in Fort Myers, Fla., the past week, but informed general manager Ben Cherington he would not be returning.

Cherington said the team is exploring internal options to fill the position.

Tuck, who was the lone holdover from fired manager Bobby Valentine’s staff, took a leave of absence last season because of personal matters.

Tuck has a good reputation for his catching knowledge and instruction. He helped in the development of former Yankees star Jorge Posada and was instrumental in the improvement of Jarrod Saltalamacchia and Lavarnway.

Former catcher Jason Varitek, now a special assistant to Cherington, could be a candidate to replace Tuck.