The Clippers squared their best-of-seven Western Conference first-round series at 2-2 with a 116-111 triumph in Dallas, but not before the Mavs erased a 31-point deficit.
George scored 26 of his 33 points in the first half to help the Clippers build their big lead despite the injury absence of Kawhi Leonard.
Harden scored 15 of his 33 in the fourth quarter, when Dallas -- led by the star duo of Kyrie Irving and Luka Doncic -- threatened to match the biggest comeback win in NBA playoff history.
Irving scored 40 points for Dallas, including a driving layup through traffic with 2:14 to play that gave the Mavs their first lead since the first quarter at 104-103.
Doncic delivered a triple-double of 29 points plus 10 rebounds and 10 assists, but in the waning minutes it was George, Harden and the Clippers who came through.
George made his first basket of the second half, a three-pointer, to put the Clippers back up 107-105 with 1:55 to play.
Harden converted a three-point play and the Clippers held on.
"Our back's against the wall, we can't go home down 3-1," Harden said of the Clippers' resolve in the face of the Mavs' bid to become the second team to rally from 31 points down to win a playoff game.
The other was the Clippers themselves, who did it against Golden State in 2019.
Knicks find a way
In Philadelphia, Brunson broke the New York franchise record for points in a playoff game and added 10 assists as the Knicks pushed reigning NBA Most valuable Player Joel Embiid and the Sixers to the brink of elimination in their Eastern Conference series.
OG Anunoby had 16 points and 14 rebounds while putting in an impressive defensive effort against Embiid.
Josh Hart grabbed 17 rebounds but scored only four points as, apart from Brunson, the Knicks struggled offensively.
"Somehow we found a way," Brunson said. "When it's ugly and you can find a way to win like that, it's a plus for us.
"We're not done yet. We've got to find a way to win another."
Embiid led Philadelphia with 27 points and 10 rebounds while Tyrese Maxey added 23 points.
With a chance to clinch the series at home on Tuesday, Brunson wasn't interested in reflecting on his franchise record.
"I'll look back when I retire," he said. "Seriously, it's great right now, helped us get a win. But it's not going to do anything for us going forward."
Elsewhere, the Milwaukee Bucks, down 2-1 in their series against the Indiana Pacers, were without Damian Lillard and Giannis Antetokounmpo in game four in Indianapolis. Lillard has a strained right Achilles tendon while Greek forward Antetokounmpo has a left calf strain.
The Minnesota Timberwolves were going for a sweep when they took on Kevin Durant and the Suns in Phoenix.
