Boston backed up their superstar, and now, they have even more motivation to ramp up their intensity moving forward. Success has been the enemy of the Boston Celtics all season. Their historic 64-win regular season was not a product of welcoming triumph with open arms. Instead, while they appreciated their accomplishments, they refused to rest on their laurels. “If we’re just going to sit back and be happy after every win, then that’s an unhealthy relationship with success, and it’s going to come back to bite us in the a**,” Joe Mazzulla said after their January 13 win over the...