Australia's Brett Rumford opened up a two-shot lead in round two of the inaugural World Super 6 Perth, as several of his countrymen enjoyed similarly impressive days at Lake Karrinyup CC.
Rumford - a co-leader alongside Englishman Mark Foster overnight - followed up his opening-round 66 with a 65 that featured eight birdies to reach 13 under.
As Foster fell away, carding a 73 to sit eight off the pace, two further Australians emerged as Rumford's closest challengers.
David Bransdon completed Friday's best round, a bogey-free 64, to get to 11 under, while Steven Jeffress is one further back after a 66.
The unique format this week will see a second cut take place after 54 holes, reducing the field to 24 ahead of a six-hole matchplay knockout phase on Sunday. Those finishing in the top eight after round three will receive a bye into the last 16.
Rumford said: "That's one less lottery round you have to deal with, isn't it? So that's definitely a huge bonus qualifying inside that top eight. It's definitely something I am thinking about.
"For any player, that's why it's going to be so unique and so interesting as well. There's sort of cuts within cuts this week and if you're not thinking about it, maybe it's a good thing, maybe a bad thing, I'm not too sure, but definitely the top eight is where you want to be."
Another home player, Lucas Herbert, and Johannes Veerman sit four behind Rumford after rounds of 68 on Friday, while the Australian trio of Matthew Millar, Adam Blyth and Daniel Fox are joined at eight under by Sebastian Heisele of Germany.
Louis Oosthuizen - a former champion at Lake Karrinyup - is among seven players tied for 10th at seven under.