With the victory, the Celtics cannot be surpassed by any team currently on the outside of the Eastern Conference playoff picture looking in.
Boston hasn't made the NBA Finals since 2010, when it lost in seven games to the Los Angeles Lakers. Two years before, the Celtics won their first title in 22 years after beating L.A. in six.
Boston has excelled under head coach Brad Stevens, who has led the team to the playoffs five times. The Celtics have made the Eastern Conference finals in back-to-back seasons but have lost to the Cleveland Cavaliers each time.
Those Cavs teams were led by LeBron James, who was on the Eastern Conference-winning team each year from 2010 to 2018 and also in 2007.
James is now a Los Angeles Laker, which could leave the Eastern Conference postseason wide-open.
The East is led by a strong five-team pack, of which the C's are a member. Getting out of the conference could be a gauntlet this year, though, with MVP candidate Giannis Antetokounmpo leading the Milwaukee Bucks and the Toronto Raptors not skipping a beat after acquiring Kawhi Leonard for DeMar DeRozan.
The Indiana Pacers aren't going away even after losing star Victor Oladipo to a season-ending injury, and the Philadelphia 76ers look ready for an NBA Finals push after acquiring Jimmy Butler and Tobias Harris midseason to a stout team that went 52-30 last year.
The Celtics also need to rid themselves of some regular-season doldrums. A 5-6 February that included a four-game losing streak highlighted the inconsistency that has plagued the C's at times this season.
Still, Boston was one win away from making the NBA Finals last year despite being without Kyrie Irving and Gordon Hayward. With those two back in the mix, the C's could make their first NBA Finals appearance in nine years.