Playing with his friend and another of the game's hottest players right now, Sergio Garcia, McIlroy quickly reduced his overnight three shot deficit and by the time he stood on the 4th tee he was ahead of the Spaniard.
He extended that lead to two with another birdie at the 5th but things were back level when McIlory bogeyed the 8th and Garcia birdied the 9th.
McIlroy established what would be a winning break with a birdie at the 11th and when Garcia bogeyed the 15th the gap was too great to bridge.
"It really started last night," said McIlroy when referring to the ground he made up quickly. "To birdie the final two holes after the rain delay last evening then the first three this morning was just what I was looking for."
McIlroy returns the number one position in the game after Adam Scott was unable to maintain the position he needed inside the top five to fend off the challenge. Scott dropped three shots late in his round and finished in a share of 8th and now falls 0.107 points behind McIlroy.
Following a season in 2013 which appeared it might go winless until the final hole of the Australian Open, McIlory has now won three titles in 2014 and it appears unlikely it will stop there.
For Garcia it continues a frustrating run of near misses, this being his third runner-up finish in his last four starts but the effort moves him to 3rd in the world ranking and surely the elusive win must come soon.
Marc Leishman continued his impressive play of late to finish 3rd, an effort that will move him inside the top 40 in the world from his current 51st.
The talk of the final day, other than the victory of McIlroy, was the forced withdrawal of Tiger Woods who aggravated his lower back when attempting to play an awkward bunker shots at the second.
A very disappointed Woods said afterwards that he does not know yet what this means for next week's PGA Championship. Wherever you sit on the popularity stakes with Tiger Woods it would a great shame to see his amazing career brought to a close through injury.
Jason Day was also forced to withdraw from the tournament earlier in the week following a bout of vertigo seemingly brought on by medication for his thumb injury and flu;
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