Iraq snatch late 1-1 AFC WCQ draw against Australia in Group B

The Socceroos have escaped with a nerve-wracking 1-1 draw against Iraq amid dreadful conditions in Tehran to leave their 2018 AFC World Cup qualification hopes in the balance.

Mathew Leckie gave Australia the lead with a 40th minute header from an Aaron Mooy corner kick but Iraq's attacking persistence paid off through substitute Ahmed Yasin's second-half equaliser.

It came as coach Ange Postecoglou boldly unveiled a brand new 3-4-3 formation at the PAS Stadium and the players took some time to adjust as they hung on for their fourth qualifying draw in a row.

Australia has three home games to come -- the next on Tuesday in Sydney against the United Arab Emirates -- and at this stage it appears they will likely need to win all of them to make it to Russia.

Predictions of a scrap-fest turned out to be on the money.

Steady rain throughout the day exacerbated what was already one of the worst pitches Australia has played on in recent years, and at times the new-look back three of Mark Milligan, Milos Degenek and Bailey Wright looked unable to cope.

Mooy's corner five minutes from the break superbly picked out Leckie, who headed home at the near post to relieve the pressure valve on the Socceroos.

It was only through some wasteful Iraqi finishing and some desperate defensive acts -- such as Mark Milligan's last-second intervention to deny Amjed Kalaf a certain goal in the 22nd minute -- that Australia was able to remain level until that point.

But the Lions of Mesopotamia kept on coming and in the 76th minute managed to square the ledger.

A terrific cross from Ali Adnan found Yasin, who scored to bring the small but vocal and largely pro-Iraqi crowd back to life in an instant.

Both teams had chances to win it in a frantic end to the match but it is undoubted that the Socceroos who will be happier with the point in the circumstances.