Celtics center Tyler Zeller not stressing about possible contract extension Posted Oct 10, 2015 Boston Celtics center Tyler Zeller has said he would like to sign a contract extension this month, but knows he should be in good shape even if he doesn't. "No stress," Zeller told HoopsHype on Thursday. "I got one more year in my contract. I know I'm going to be here anyway." (MassLive.com)