Melbourne United coach Dean Vickerman has demanded answers after a “crazy” decision denied Matthew Dellavedova a match-winning free throw before Perth upset his team in overtime.

Perth improved a horrible road record and shot life into their season with a dramatic 102-95 Monday night defeat of the ladder leaders.

The one-sided extra period came after a rollicking final 90 seconds of regular time, when both teams thought they’d done enough to win the game multiple times.

Jordan Usher was rocks or diamonds in those moments; hitting a three-pointer to give Perth the lead then, with the game tied, missing both free throws when just one would have sealed a win in the final second.

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United battled injuries to three of its starting five but still looked to have found a way to improve to 9-1 behind the returning Dellavedova (23 points, six assists).

The NBA championship winner thought he had earned a chance to seal the game at the stripe when he was fouled while scoring a tough lay-up with one second to play.

But the foul was reversed after a Perth review, the two points standing to tie the game before Usher’s free throws rimmed out in a final twist to an incredible regular-time climax.

United coach Dean Vickerman rued a lack of execution at crucial moments but saved a blast for the officials in his post-game press conference.

“I go back and watch it after the game and say (Perth’s Alexandre) Sarr hit Delly on the arm,” he said of the call that was reversed in the final second.

“Someone is going to have to tell me what happened on that play … we should be shooting a shot for the win.

“To overturn that is crazy.

“When things decide a game we need to get the film … we need (clarification) as quickly as possible.”

Dellavedova was back after a four-game absence due to concussion but United has a new head injury concern after Luke Travers fell while driving to the hoop in the first minute of the game and headbutted teammate Ariel Hukporti’s knee.

Travers played no further part, while Hukporti returned with his knee strapped and battled in a 10-minute effort. He could be in doubt for their next clash, with South East Melbourne.

United’s woes were compounded when Ian Clark grabbed at his troublesome hamstring in the second period and was put on ice.

Jo Lual-Acuil (25 points, 10 rebounds) put United on track for a backs-to-the-wall victory but Perth wouldn’t go away as they clinched a pressure-relieving win for coach John Rillie.

Bryce Cotton (24 points) injected himself after a quiet first half while Kristian Doolittle (18 points, seven rebounds, five assists) was assured and Jesse Wagstaff played a calm bench cameo.

It was just Perth’s second win from its past 10 road trips and improved the Wildcats to 4-5 after a victory over Adelaide 36ers on Saturday snapped a four-game losing streak.

“We just found a way,” Rillie said.

“I only care about how our team plays … everyone can have their opinion but Stevie Wonder saw we weren’t playing good.

“If you really believe in your team it usually works itself out.”

-AAP