Julius Randle and Immanuel Quickley combined for 46 points as the in-form New York Knicks upset the Boston Celtics 109-94 in the NBA on Monday.

Randle and Quickley finished with 23 points each as the impressive Knicks extended their winning streak to six games at Madison Square Garden.

The New York victory bumped the Celtics out of the top spot in the Eastern Conference standings, lifting the Milwaukee Bucks into first place.

Six Knicks players finished the game in double figures after New York took control of the contest early on to lead almost from start to finish. The Knicks moved up to fifth place in the East after the win.

New York pulled 20 points clear midway through the second quarter and retained a comfortable advantage throughout.

A miserable night for Boston ended with Jayson Tatum being ejected with four minutes remaining for a second technical foul.

Tatum — the hero of Boston's pulsating victory over Philadelphia on Saturday — endured a frustrating outing, making just six-of-18 from the field.

Malcolm Brogdon led the Boston scorers with 22 points.

Elsewhere on Monday, Jimmy Butler scored 23 points as the Miami Heat sent the Philadelphia 76ers spinning to a second straight defeat with a 101-99 victory on the road.

A superb defensive effort from Miami saw the potent Sixers offense – which has been averaging 114 points this season — restricted to fewer than 100 points.

At the other end, Butler provided offensive guile and came up clutch in the final two minutes, giving Miami a 100-99 lead with a remarkable driving reverse layup shortly before drawing a foul and two free throws that put the Heat into a winning position.

In addition to his 23 points, Butler finished with 11 rebounds, nine assists and four steals.

Taking a stand 

Four other Miami players finished in double figures, with Gabe Vincent adding 14 points while Max Strus and Bam Adebayo chipped in with 13 points apiece.

The victory was a welcome return to form for Miami, who were beaten by the lowly Charlotte Hornets on Saturday after being routed by Milwaukee on Friday.

"Things don't always go your way in this league and it's about how you respond collectively when you have some disappointments," Heat coach Erik Spoelstra said.

"We were all disappointed about the last two games, and at some point you just have to take a stand, figure it out and gut out a win."

The Sixers meanwhile were left ruing a lackluster first-half display that left them chasing the game throughout.

Joel Embiid led the Philadelphia scorers with 27 points while Tyrese Maxey scored 23 and James Harden 20.

Sixers coach Doc Rivers said his team had shown signs of weariness after roller coaster games against Boston and Memphis last week.

"We were flat in the first half," Rivers said. "We had two games with a lot of energy and you could just feel it really.

"The way we looked at it early on was 'Let's just try and get to half-time.'

"I just thought we were really sloppy tonight, sluggish. It happens.

"But in those close games, you've still got to find a way to win. And tonight we didn't."

Miami improved to 33-29 with the victory while the third-placed Sixers slipped to 39-21.

In other games on Monday, the Charlotte Hornets defeated the Detroit Pistons 117-106 in a battle of the bottom two clubs in the Eastern Conference.

Charlotte's victory was overshadowed by an injury to star guard LaMelo Ball, who left the game after suffering a fractured right ankle.