Golf showman Min Woo Lee pleaded with fans to tone it down before sending the masses back into a frenzy on an electric afternoon at the Australian Open in Sydney.

Lee is firmly on track to complete a golden winning double of Australia's two flagship summer events after seizing a commanding three-shot halfway lead at the Open with a sublime second-round 64 at The Australian on Friday.

The freshly crowned Australian PGA Championship winner ignited the big gallery following the game's new superstar when he holed out from a greenside bunker on the par-3 fourth before continuing his birdie blitz with five more plus an eagle in a magical 11-hole stretch.

While he iced his round with a tap-in eagle at the last, after knocking his dazzling mid-iron approach from the pine needles to within a metre, the defining moment of Lee's round came on the par-4 16th.

About to putt, Lee pulled back, gestured to spectators to shush before coolly resetting and draining a a 12-footer, prompting a deafening roar from his legion of fans.

He offered a thank you to the crowd after surging ahead of Scot Connor Syme on a truly cosmopolitan leaderboard.

Six different nationalities occupied the top six positions late in the second round.

At 12 under, Lee looked in control with his three-stroke buffer over Syme, who posted a 70 at The Lakes on Friday morning.

Chilean star Joaquin Niemann and Venezuela's Jhonattan Vegas are both eight under after a pair of 69s at The Lakes.

Rounding out the eclectic mix of contenders is Dutchman Lars van Meijel at seven under.

Australians Jeffrey Guan (66, The Lakes) and Sam Jones (67, The Australian) are among a bunch of players five shots adrift of Lee.

After being in danger of missing the halfway cut, heavyweight home hopes Adam Scott and Cameron Smith both survived the chop and will enter the final two rounds at The Australian at four under.

Smith ruefully threw a ball in the lake after bogeying the penultimate hole in his three-under 68 playing alongside Lee, while Scott carded a 68 at The Lakes.