It was a case of Aussie, Aussie, Aussie at the top of the leaderboard at the Bay Hill Invitational, led by a great performance from Jason Day. Day fired a six-under 66 in a rollercoaster opening round that included seven birdies, one eagle, one bogey and one double-bogey. He is one shot ahead of a group of five players that includes fellow Australians Adam Scott and Marc Leishman, who earlier shot a pair of bogey-free, five-under 67s. "I drove it pretty well today, drove it on a string. I think I played the par-fives in five-under so that definitely helps," Day said. "You have to capitalise on the par-fives here because [the course] does yield a lot of birdies if you're playing from the fairway. 
"It was one of those days where everything went well."
The only thing that didn't, a pulled hook that sailed left and out-of bounds from the tee on the par-four ninth, led to a double-bogey.
For Day it was simply a matter of reset and forget on the next one.
"That was the only one that was weird, because I was driving it very well, hitting my irons great and putting and chipping well too," he said. "It was just one bad swing ... just had to trust myself, go out and try and fight on the back side."
Day did more than fight. His back nine was Day at his best. Crisp and aggressive.
Birdies at 12, 13 and 15 were followed by a magnificent eagle at the par-five 16th and he got up and down from around the greens on par-threes 14 and 17 and the par-four 18th. The eagle on 16 the highlight of the round for Day.
"Just a six iron, 190 yards, it was perfect length to cover the water and I couldn't hit it on a better line and I just had a little left-to-right putt from 10 feet," Day said as he recapped the shot.
Of the other Aussies, Matt Jones is two-under and Ryan Ruffels is even par and Aaron Baddeley shot a four-over 76.