Prior to Dec. 8, the Chicago Bulls were officially the complete opposite of the best team in the NBA. They were 3-20, owners of the worst record in the league.

But on Dec. 8, Nikola Mirotic finally made his season debut, and that’s when the Bulls’ fortunes quickly turned for the better. Twelve games and a few weeks later, the Bulls are officially the best team in the NBA during that stretch.

The transformation the Bulls have undergone upon Mirotic’s return to the lineup has been remarkable. Mirotic himself has obviously had a lot to do with their improvement thanks to his terrific production. Excluding his first game back, Mirotic is averaging 19.2 points and 7.7 rebounds while shooting 51 percent from the floor and 49 percent on 3-pointers.

But beyond his actual play on the court, Mirotic also had a tremendous impact on the team by the way he and Bobby Portis were able to get past their traumatic incident earlier in the season and co-exist on the court. It can’t be underestimated how that feel-good factor has helped spur the team on to the heights they’ve reached.

Chances are the Bulls will come back down to earth sometime soon. But when they do, they can still proudly look back at this period and how they went from the worst team in the league to the best, even if it was only over a few weeks.