Goals from Iraqi striker Emad Mohammed in the third and fourth minutes gave the Asian Champions League runners-up the perfect start while leaving the New Zealand part-timers with an insurmountable task.

Abdul Wahab Abu Hail added a third for Sepahan two minutes into the second half before an own goal from Hadi Aghily in the 74th minute gave Waitakere some reward for their hard work.

"We had five minutes of madness at the start of the game and at this level you can't make the errors that we did," said the former Leeds United defender.

"We had a plan to counteract their best player, (Moharram) Navidkia, and he didn't play and I think that threw us a bit. We sat back and gave them too much respect and it was only in the second half that we pushed up.

"It's frustrating because we made such stupid errors and it's hurt us badly."

Hay's anger at the manner of the defeat was echoed by the club's head coach Chris Milichich.

"It's a huge disappointment because there were seven minutes when we made three errors and that's cost us three goals," he said.

"We woke up in the 50th minute and we started to get into them and then things changed."

Sepahan will now face Japan's Urawa Reds, who defeated them in the final of last month's Asian Champions League, and coach Luka Bonacic is relishing the rematch.

"We won, so finally we can talk about the match against Urawa," said the Croatian.

"Yesterday I was asked about Urawa and I was not comfortable about that because we should respect Waitakere.

"We lost to Urawa in the final of the AFC Champions League, so therefore Urawa are Asian champions and we are honoured to play against Urawa one more time. I'm happy that we can do so."