NBL referees boss Scott Butler has conceded officials "made a mistake" to deny Melbourne United a potential match-winning free throw, even though the decision to reverse the call on review was correct.
The frantic conclusion to Monday night's overtime win by Perth left United coach Dean Vickerman unimpressed and demanding answers from the officials.
Dellavedova tied the game with 1.8 seconds of regular time remaining with a tough lay-up and, after a pushing foul was called on the play, was set to shoot a free throw to likely win the game for his side.
But Wildcats coach John Rillie successfully reviewed the foul, and Perth then missed a chance of their own to win in regular time when Jordan Usher was fouled but missed both free throws.
"I go back and watch it after the game and say (Perth's Alexandre) Sarr hit Delly on the arm," Vickerman said post-game of the decisive call.
"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."
On Tuesday afternoon that clarification arrived following an NBL review unlikely to soothe Vickerman and his ladder-leading team.
"In this instance, it was correctly determined there was no pushing foul on Sarr, and the decision was correctly overturned," Butler said.
“We do acknowledge a mistake was made on that play.
"Sarr should have been called for a hands foul, which would have resulted in Dellavedova going to the foul line."
No-calls cannot be changed or challenged via the coaches challenge, with the coach only able to contest the ruling of the foul that was called.
Butler said the pushing foul on Usher, adjudicated to have occurred after the ball had left the hands of the inbounding Perth passer, was correctly awarded as two free throws and not a throw-in foul.
United declined to comment on the findings of the review when contacted by AAP.
Perth's upset win moved them to 4-5 ahead of hosting the New Zealand Breakers on Friday.
Despite their defeat on Monday, United (8-2) retain an outright lead at the top of the ladder ahead of Sydney (6-3).