“I cannot say it enough. Boston, you’ll always be a part of who I am.#THANKYOUBOSTON,” Pierce wrote.
Pierce was traded to the Brooklyn Nets along with Kevin Garnett and Jason Terry this offseason.
Pierce played 15 years in Boston after being drafted by the team in 1998. He finishes as the Celtics second all-time leading scorer to John Havlicek.
“I cannot say it enough. Boston, you’ll always be a part of who I am,” wrote Pierce on Twitter.
Last week, the Celtics took out a full-page ad in the Boston Globe to thank Pierce and Garnett.