Eastern Conference top seeds Boston, stunned at home by the eighth-seeded Heat on Wednesday, responded with a comprehensive victory in Miami.
The Thunder, winners of their first two games against the Pelicans in Oklahoma City, pressed their advantage in New Orleans with a 106-85 thrashing that gave them a 3-0 stranglehold on the best-of-seven Western Conference first round series.
The Orlando Magic authored another big win, beating the Cleveland Cavaliers 112-89 to level their Eastern Conference series at two games apiece, while in the final game of the day LeBron James and the Los Angeles Lakers, down 0-3, sought to fend off elimination against the reigning champion Denver Nuggets.
In Miami, Jayson Tatum and Jaylen Brown scored 22 points apiece, Tatum adding 11 rebounds and six assists as the Celtics led from start to finish.
Kristaps Porzingis scored 18 points and Derrick White chipped in 16 for the Celtics, who allowed the Heat the fewest points of any Celtics opponent this season.
"That's where we're going to win games at, on defensive end," Tatum told broadcaster TNT, adding that even if shots aren't falling "if you can get stops, you can figure it out."
Boston appeared to have this one figured out early, leading 21-12 after the first quarter before erupting for 42 points in the second period.
They were up by 24 points at halftime, having dominated every facet of the game and scored 19 points off Miami turnovers. They pushed the lead to as many as 29 in the second half.
Miami, who had just nine three-pointers after raining 23 treys in their game two victory, will try to regroup when they host game four on Monday.
That's when Shai Gilgeous-Alexander and the Thunder will have a chance to close out the Pelicans in New Orleans.
With Zion Williamson sidelined with a hamstring strain, the Pels have had no answer for the young Thunder team led by Most Valuable Player award finalist Gilgeous-Alexander, who led the Thunder on Saturday with 24 points five rebounds and eight assists.
A three-pointer from Gilgeous-Alexander launched a 14-0 Thunder run late in the second quarter that put Oklahoma City in control for good.
The Thunder drained 17 three-pointers and after taking a 60-46 lead into halftime pushed their advantage to as many as 24 points in the fourth quarter.
Jalen Williams and Josh Giddey scored 21 points apiece for the Thunder.
Brandon Ingram led the Pelicans with 19 and CJ McCollum added 16, but New Orleans made just nine of their 32 three-point attempts and turned the ball over 21 times.
Magic rout Cavs
In Orlando, Franz Wagner scored 32 points and the Magic dominated Cleveland in the second half.
The Cavs scored just 10 points in the third quarter and 29 in the second half, going more than six minutes without scoring as the Magic took a 92-70 lead early in the fourth quarter.
With Magic star Paolo Banchero struggling to just nine points and four rebounds, Germany's Wagner filled the void, grabbing 13 rebounds with four assists and a blocked shot.
Jarrett Allen led Cleveland with 21 points and nine rebounds with Cavs star Donovan Mitchell finishing with 18 points.
"Our guys made the right adjustments," Magic coach Jamahl Mosley said of his team's recovery from a nine-point halftime deficit.
"(They) realized it was about the body and ball movement, sharing it, moving it, trusting the pass," Mosley said, calling their defensive effort "special."
