Both Australians signed for 5-under rounds of 65 to be T3 early in the day but slipped down the standings as Ian Poulter raced to the top of the pack with an 8-under 62.
Fellow afternoon players Rickie Fowler and Si Woo Kim also passed the Australians late in the day on a packed leaderboard which sees 26 golfers within five shots of top spot.
Day played alongside eight-time winner of the tournament Tiger Woods, the former World Number One making a frustrating bogey on his final hole to post 4-under 66 and be T14.
Day was blemish free in his round despite saying later he didn’t have his best game tee to green, the statistics confirming that with just 50 per cent of fairways hit.
However, the Queenslander’s iron play was sharp with 94 per cent of greens found in regulation and a hot putter kept the momentum going with 1.62 strokes gained on the field for the day.
Leishman’s card wasn’t quite as neat, two bogeys sprinkled among seven birdies though the Victorian was pleased enough with his play.
“Really happy with the start,” he said after the round. “My iron game was solid and every time I was in a decent spot I was thinking about making birdies and that makes the game a bit easier.
“And when you birdie all the par-3’s that helps, too.”
Two of those par-3 birdies came during a front nine run that included four in five holes with a bogey sandwiched in at the fourth.
“On four I hit two really good shots and then a terrible putt about 15 feet past the hole which was a disappointing bogey,” he said.
“but to bounce back with three birdies in a row on not the easiest three holes was really good.”
Poulter’s lead is one over Kyle Stanley and Rickie Fowler with Patrick Cantlay, Jon Rahm and Si Woo Kim all at 6-under.
The Australian pair are part of a seven-way tie for seventh at 5-under which includes Rory McIlroy and Justin Thomas.
World Number One and last week’s winner Dustin Johnson signed or an adventurous 1-under 69 to be T39.
There are five Australians in the field this week with 2011 winner Adam Scott signing for a 2-under 68 to be T27 and Wade Ormsby one further back and T39.
Cameron Smith was at less than his best and posted an even par round to be T47 in the 71 player field.
FEATURE CLUB - SANCTUARY COVE, PALMS COURSE, QUEENSLAND:
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