Australian guards Dante Exum and Josh Giddey have both come up big for their NBA clubs in crucial wins in the lead-in to the play-offs.

Exum forced overtime with a buzzer-beating three-pointer on Sunday (Monday AEST) as the Dallas Mavericks rallied from 22 points down for a 147-136 NBA victory over the Houston Rockets.

Kyrie Irving scored a season-high 48 points and Luka Doncic had 37 points, 12 assists and nine rebounds as the Mavericks took another step towards the fifth seed in the Western Conference play-offs.

Dillon Brooks scored a season-high 29 points for the Rockets, who were eliminated from post-season contention.

With Houston leading by three with 8.3 seconds to go in regulation, Jabari Smith Jr missed two free throws.

Dallas were out of timeouts, and Exum scrambled up the court and passed to Doncic.

The Dallas superstar dribbled towards midcourt and faked a shot before passing back to Exum, whose three over Smith beat the buzzer.

“I just went and grabbed it and tried to get the ball to Luka,” Exum said.

“Luka is great knowing that two guys are going to double him and trusting his teammates.”

Exum ended the game with 14 points and nine rebounds.

Not to be outdone, Giddey filled up the scoresheet with his 11th career triple-double as the Oklahoma City Thunder edged past Charlotte 121-118.

Giddey finished with 20 points, 13 rebounds and 13 assists as the Thunder (53-25)  firmed up their hold on third place on the Western Conference standings.

The Thunder had lost their previous three games with stars Shai Gilgeous-Alexander and Jalen Williams out with injuries.

But Aaron Wiggins stepped up with 26 points and Chet Holmgren had 20 points and 10 rebounds to provide strong support for Giddey.

“We weren’t great in a lot of areas, and it was an ugly one,” Giddey said.

“But at this part of the year you take the wins you get. Now hopefully we can close out the regular season the right way.”

Charlotte’s Brandon Miller missed a three-pointer at the buzzer that would have sent the game to overtime.

Although Exum and Giddey were the star turns, a couple of other Australians expected to feature prominently at the Paris Olympics, Dyson Daniels and Joe Ingles, also stepped up on Sunday.

Daniels had 10 points and was one of five New Orleans players in double figures as the Pelicans beat the Phoenix Suns 113-105 in another match with important Western Conference play-off implications.

The sixth-placed Suns and seventh-placed Pelicans now share identical 46-32 records with four games of the regular season remaining.

It was New Orleans’ first win over Phoenix in their past five outings.

Veteran Ingles had nine points and five assists as the Orlando Magic – who sit third in the Eastern Conference – improved to 46-32 with a 113-98 win over the Chicago Bulls.