The Australians began the day at nine under – a stroke shy of first round pacesetters Scotland – and South Africa started from joint 22nd with Finland, Iceland, Italy and the host nation Mexico after a one-par 141 at the Mayakoba El Camaleon Golf Club.
Harrison Endycott and Cameron Davis produced a pair of 66s for a 10-under 132 at the Mayakoba, which vaulted the four-time champions into pole position, while Curtis Luck – the 2016 US Amateur champion, added a non-counting even-par 71.
Australia’s 36-hole total of 19-under-par 267 is one shot off the WATC record set by the USA in 2012.
South Africa, meanwhile, followed on with an even-par 144 at the berostar Playa Paraiso Golf Club to join Brazil in a tie for 29th.
“It was regrettably another frustrating day for the boys,” said manager Eden Thompson.
“Jovan Rebula led the way with a two under 70, while Marco Steyn and Dylan Naidoo returned a pair of 74s. Every time they looked to be moving in the right direction, they would just miss a shot in the wrong place which can be costly and, in a field of this quality, those small mistakes are magnified.
“Marco was first off and he hit the most perfect drive down the 10th. His ball landed 75 metres from the green in a massive divot. He tried to dig it out, but just caught the ball a little thin and it skidded through the rough behind the green deep into the small forest beyond. He chipped out, chipped on but could not make the eight footer for bogey and got off to a double bogey start.
“Marco is really is playing a lot better than his suggests, but another trio of three-putts and the occasional loose shot proved just too costly.
“Dylan continued to battle off the tee early in the round but he never let up and his fighting spirit kept him going. His iron play once again saved the day. I advised him after nine holes to forget about hitting the driver and focus on getting the ball in play off the tee and then play to his strengths. To his credit, he managed to see the lighter side of his wayward driver.
“He advised me that his ‘chip outs’ were slowly becoming one of his stronger suites and he managed to find a swing late on the back nine. He hit two great shots into the par five ninth, which put him in a better frame of mind. Now he just needs to get the putter going, as well.
“Jovan was really steady again and his two under 70, by his own admission, was about the worst score he could make. He made plenty of really good swings and where he did hit a weak shot, he managed to fight for the pars including a great chip to save par at his 15th hole. The putter is still a little too cold, but hopefully he gets in going in the third round.
“We are now well behind Australia, but we will use the next two rounds to try and post solid scores to see how high we can get up the leaderboard.”
Meanwhile the world’s top ranked amateur, Maverick McNealy, and Scottie Scheffler produced a pair of 69s at Iberostar to advance the USA into second place at 11-under 275.
Switzerland moved into third at 10-under 276 and Poland finished a stroke back in fourth. Scotland slipped to fifth at eight under 278, while 2016 Sanlam SA Stroke Play champion Jack Hume helped Ireland to a tie for sixth with Austria at seven under.
England, Chinese Taipei, Colombia and Norway rounded out the top 10 at six under.