The Socceroos need a win from their fifth fixture of the final group stage to go three points clear of Iraq, Oman and Jordan and FC Utrecht full-back Zullo is aware that it is an extremely vital clash prior to their final three matches.
"We have the three home games from our last four qualification matches to come and we want to get the job done before we face Iraq at home in our final qualifier (18 June) because that would bring a lot of unwanted pressure with it," he told SBS.
"This game against Oman could be the turning point of our qualification campaign. If we win it changes everything for us.
"If we accomplish that then if we get something in Japan in our next qualifier (4 June) that's going to be a huge bonus.
"But the games we need to focus on more than anything are these three home games - against Oman, Jordan and Iraq.
"I know what Holger (Osieck) is like and he won't be worrying about equations and what we need to do - he will just be going after all 12 points still on offer in the group.
"It's good to have these home games but it would have been nice to have had some of them at the start of the qualifying campaign and we could have got into a nice rhythm.
"But those are the cards we have been dealt and we'll play them as best we can."