With their victory, the Celtics proved what was already clear before the game. Now 4-0 on the season, the defending champions are the class of the NBA and the Bucks will need to work to get to where they can attempt to challenge Boston in the postseason. “They’ve been around for years now and you cannot replace that. You cannot,” Bucks star Giannis Antetokounmpo said after putting up 30 points, 10 rebounds, six assists but also seven turnovers in Monday’s loss. “You can put the best players together, but just knowing how to play with one another, sacrificing for one another, playing the right way, knowing where your teammates are going to be, knowing who’s going to take over, who has the hot hand — that’s what winning teams do. “And our goal is to get there. Right now, obviously we’re not there, but I don’t think we are far off. I don’t care about the record. I just care about keep on building, keep on being healthy and get to where we want to get.”