Cameron Smith is keeping Marc Leishman at arm's length as the Australian PGA Championship drawcards slug it out on a slow-moving Saturday at Royal Pines.

Defending champion Smith had improved by two to 11-under after 10 holes on the Gold Coast while a birdie on the 10th helped Leishman do the same to remain just one shot back.

Playing in the group ahead of the star Australian pair, Australian Order of Merit leader was nine-under after 11.

Read Next With the tee on the eighth moved forward 30 metres an eagle became an option at the par four.

But Smith's drive bounced off the back of the green and he was too heavy with his chip back, two-putting to take a par.

Leishman's chip was good enough for an easy birdie, but Smith bounced back on the ninth with a birdie of his own to continue the tit-for-tat battle.

McLeod hung tough with birdies on the first and the tenth holes to put a gap on playing partner Dimi Papadatos (six-under), who is also vying of Order of Merit honours.

Braden Becker moved into calculations after carding 67 and returning to the clubhouse at six-under, while Matthew Millar (seven-under) did the same.

America's Harold Varner III, a champion in 2016, went bogey, birdie, birdie, birdie, bogey either side of the turn to be seven-under after 12 holes.

And Englishman Andrew Johnston had picked up one shot but narrowly missed a number of birdie efforts to be six-under after 12 holes.