Boston's Jayson Tatum and Jaylen Brown sank 30 points each as the Celtics thoroughly defeated Nikola Jokic's Denver Nuggets 124-104 on Sunday.
Tatum and Brown spearheaded a superb all-round offensive performance for Boston, whose defense successfully bottled up the threat of Denver's reigning NBA MVP Jokic, who was held to 23 points.
Apart from a brief spell in the first quarter, Boston led throughout, pulling clear of Denver with a 35-16 second quarter which included four 3-pointers from four attempts by Payton Pritchard.
That left Boston up 68-43 at half-time and, although Denver tightened up after the interval, the result was never in doubt as Boston cruised to a third straight victory.
The Celtics improved to 44-28 with the win to remain fourth in the Eastern Conference, level on 44 wins with third-placed Milwaukee.
Denver dropped to 42-30 in the Western Conference, and are one place outside the automatic playoff places.
Elsewhere on Sunday, Philadelphia were out-hustled in a low-scoring 93-88 loss to the Toronto Raptors.
The Raptors held 76ers big man Joel Embiid to 21 points as defenses dominated at Philadelphia's Wells Fargo Center.
James Harden, who finished with 17 points, gave up a late flagrant foul to end the Sixers hopes of forcing overtime.
Pascal Siakam led the Raptors scorers with 26 points.
In Sacramento, Devin Booker scored 31 points as the Western Conference-leading Phoenix Suns survived a scare before seeing off the Kings 127-124 in overtime.
Sacramento led by 14 points early in the second half against a sluggish Suns, before Booker sparked a fightback with a 19-point third quarter.
Booker's rally trimmed Sacramento's lead to just four points heading into the fourth quarter, and from there Phoenix gradually clawed back the advantage before squeaking through in overtime.
Booker was backed with 27 points from Mikal Bridges and 21 points from Landry Shamet.
Rookie Davion Mitchell led the Sacramento scorers with a career-high 28 points.
Phoenix, who have already qualified for the playoffs, improved their record to 58-14 at the top of the West, extending their unbeaten streak to five games.
"It's gratifying just because of so many guys stepping up and making a contribution," Phoenix coach Monty Williams said afterward.
"Everybody on our team that had a uniform on had a chance to impact the game ... it says a lot about who we are as a team. Just proud of the mental toughness we had, the way we stayed with it."
The Kings slipped to 25-48 and are 13th in the division, their faint chances of securing a place in the postseason play-in tournament fading rapidly.
The Memphis Grizzlies remain in second place in the West. The Grizzlies shrugged off the absence of Ja Morant to thrash the Houston Rockets 122-98 in Texas on Sunday.
Desmond Bane led the Memphis scorers with 24 points to take the Grizzlies to 49-23 – nine games back from leaders Phoenix.
In San Francisco, Keldon Johnson scored from a free throw rebound with 0.3 seconds remaining to give the San Antonio Spurs a dramatic 110-108 victory over the Golden State Warriors.
Josh Richardson led the Spurs scorers with 25 points against a Warriors team missing injured star Steph Curry.
The Warriors are third in the West with a 47-23 record.
