The Celtics have been clear throughout the season: They care about the NBA Cup. Sure, it’s not the playoffs, but it’s still something they can win during the regular season. So with the C’s fighting to make the knockout stages late against the Bulls, they played right up until the final buzzer Friday in Chicago for point differential purposes.

Even though the Celtics were already up six points on the Bulls with just seconds left, they still called a timeout with 1.4 seconds left. That allowed them to advance the ball and also get one more possession to keep up the point differential. They ended up getting a Sam Hauser 3-pointer to secure the nine-point win over the Bulls. And C’s coach Joe Mazzulla said postgame he enjoyed that rules aspect of the NBA Cup.

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“I like it because this tournament and the point differential kind of eliminates the unwritten rules that you’re supposed to follow or not follow,” Mazzulla said postgame, via NBC Sports Boston. “Where in a normal situation, you wouldn’t do that. But in this one, you get to draw up a play and try to get better in that situation. So guys did a good job executing and we tried to extend the point differential as much as we could.”

It’s the second straight season the Celtics needed to run up the score on the Bulls. The C’s needed to win by at least 23 points last season, which they did as they advanced to the knockout stages of the NBA Cup. This year, the C’s needed to up their point differential as much as possible after the Hawks beat the Cavaliers earlier Friday.

The Atlanta win means Boston’s lone path to the knockout stages of the NBA Cup is as a wild card, which is the best second-place teams in the three East groups. So, the tiebreaker comes down to point differential. Here’s a look at what exactly the Celtics need to happen Tuesday so they can get to the quarterfinals of the tourney.

The league introduced the in-season tournament last year and it’s added some new elements to the regular season. Not only are games more competitive on these flashy courts, but point differential hasn’t often mattered in the league. So now, there’s a little bit more juice to some of these games, and some guys are going to enjoy that.

“It’s different,” Mazzulla said. “I think they enjoy it. It adds a little life to the game in the regular season. I know Sam likes it anytime he can get a shot up.”