At 7-under, the local product of Melbourne sits one ahead of American Matthew Goggin, while fellow Aussies Paul Gow and Michael Clayton are two back following opening rounds of 67.
Allenby, who not only won this event last year, but also collected two wins on the U.S. PGA Tour, has emerged as his countrys finest golfer.
Yet, even he wasnt quite satisfied with his bogey-free round on Day 1.
'I struggled with my swing all round. It hasn't been as sharp as I would have liked it to be in the last three or four weeks,' Allenby said. 'But Im not complaining with 7-under, I'll take that.'
While he struggled with his swing, there were no problems in the putting department as the 30-year-old required just 23 strokes with the flatstick.
Every time I hit the green, I made the putt,' he said. 'I holed a 10-footer for par to start the day, then I had to hole an eight-footer at the 11th hole for par as well. The par-3 14th, I plugged it in the front trap and holed a 20-footer for par.'
As Australias current No. 1 player, Allenby has taken over the reigns of legend and recent inductee to the World Golf Hall of Fame Greg Norman.
Yet, while Normans form has been waning in recent years, he showed he still has some magic left on Thursday, as the Great White Shark carded a 4-under 68 to join an eight-way tie for fifth.
'I played pretty good today,' said Norman. 'I felt like I could have putted a little better because the greens were rolling this morning. All in all, it was a very positive day.'
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