Celtics guard Isaiah Thomas said his team and its coaches quit on Friday. BOSTON — As a large media contingent filled the hallway around Warriors guard Klay Thompson, who scored 28 points in a 104-88 victory against the Celtics that was far worse than the final score, a few reporters made their way into the losing locker room, where Isaiah Thomas was holding court. With Thomas as the face of the franchise, Boston has steadily improved each year, enough to earn preseason predictions as the Eastern Conference's second-best team.