"I am part of the World Cup programme but the final decision (on referees) will be made in February 2014. There are 52 other referees around the world vying for 24 spots.
"At the moment it's an open list so if I make a mistake, my name may be removed from the list. There's someone there (FIFA) to view me in my games that I do in the weekends," he said.
O'Leary is following a specific training guide, including filling logs, sending heart-rate data once a month and tests on the laws of the game that are monitored by FIFA officials in Malaysia and Zurich.
Though never a good player himself and felt uncomfortable as a coach, he always wanted to be involved at the elite level of football and his first break came 21 years ago when a friend inspired him to take up the whistle.
"That hunger for refereeing is definitely there. For me, the World Cup is the pinnacle ... it's the cream of the cream and I've got to be optimistic while at the same time realising that the road is tough."
He makes special mention of his first international match as a referee - Australia and the Solomon Islands in Honiara in 2004, especially the security briefing prior to the game in light of ethnic tension on the island.
Tikipunga High School principal Peter Garelja described O'Leary as a living example of excellence whose sporting skills were being used to teach positive behaviour in students.
"He's proved that you can live and work in a small city like Whangarei and still be an x-factor on the world stage."
The New Zealand Referee of the Year in 2012, O'Leary was also selected to officiate at the London Olympics in 2012.
In 2008, he became the first New Zealander to officiate in the English Premier League when he was fourth official in the clash between Aston Villa and Sunderland in Birmingham.
O'Leary was a guest of top English referee Steve Bennett.
