It’s been an interesting offseason for the Boston Celtics. With Brad Stevens in his new role leading the front office, the Celtics didn’t make a massive splash, but they flipped Kemba Walker in a deal for Al Horford, acquired Josh Richardson and landed Dennis Schroder on a one-year bargain contract to bolster their backcourt. However, Boston wasn’t done as mid-August arrived, as word broke on Monday that veteran guard Marcus Smart will be sticking around on a four-year extension that will keep him under contract through the 2025-26 season.