Both teams went into Saturday night's meeting at John Cain Arena with a 2-1 record in the NBL's new tournament but Melbourne fought back in the second half to claim a key win against their fierce rivals.

United came from 13 points down to lead 79-73 with less than two minutes to play but Casper Ware sank a pair of floating jump shots to give the Kings one final chance at victory.

However Ware could not strike the final blow against his former club, missing a potential game-winning three-pointer in the final seconds.

"Our defence was really committed and I thought we rebounded really great in that second half as well," said coach Dean Vickerman after United won their third in a row despite missing injured starters Chris Goulding (calf) and Jack White (finger).

Vickerman also praised the play of Shea Ili (four three-pointers) and Yudai Baba (11 points) as the guard duo produced a series of key plays during a tense final quarter.

"There was all kinds of little cameos tonight and everybody chipped in - it was a really good team win."

Jock Landale paced United with 20 points and eight rebounds, Scotty Hopson added 14, and Mitch McCarron compiled 13 points, six assists and five rebounds.

Guard Dejan Vasiljevic has been a revelation for the Kings in his rookie season, the 23-year-old scoring 17 points in the first half on his way to a team-high 22 while Ware added 21 and Shaun Bruce 17.

The Kings controlled the tempo to lead 43-34 at halftime but a 22-11 start to the third quarter saw United hit the front for the first time.

A failed coaches' challenge on a Ware foul proved costly for the Kings as Melbourne stormed back into the contest while coach Adam Forde hesitated using his final timeout.

"I definitely blew that and I'm going to look back on that and reassess how much I want to gamble on that challenge when it was silly of me to do that," Forde said.

"In a stretch of four minutes and 26 seconds, they go on a 16-2 run and that's the ball game."

While Melbourne currently hold top spot on the NBL Cup and regular season ladders, the Perth Wildcats sit one point behind them in the cup competition with one game in hand.

Australian Associated Press