Martin Maritz and Tyrone Mordt shared the lead after round one of the Joburg Open today with both carding faultless nine-under-par 62s, although they came on different sets of 18 holes at the Royal Johannesburg and Kensington Golf Club.
The two South Africans registered nine birdies each, including four in a row on the back nine, with Maritz's effort coming on the longer and arguably tougher east course, to lead by a shot from compatriot Branden Grace following his earlier 63.
This week's co-sanctioned European and Sunshine tour event is being played over two courses on the first two days - the rounds are divided between the par-71 east and west courses, before the cut is made and the final two rounds are played on the east side.
Another local Thomas Aiken also excelled on the east after his 64 put him a on seven under and left him as the only other player in the top 10 to have gotten the more difficult 18 out of the way.
Also on that score was Frenchman Alexandre Kaleka, while eight players were a further stroke back on six under after 65s.
Among them were Britons Stuart Manley, Jamie Elson and Robert Dinwiddie along with Norway's Marius Thorp, Dutchman Floris de Vries and South African trio Peter-Henric McIntyre, Garth Mulroy and Divan van den Heever.
The man they were all chasing was Maritz, who has never won a tournament on tour and who recently took a break from professional golf due to frustration over his game.
Speaking after his round, which saw him begin with successive birdies, add a further two at six and eight and then conclude with five birdies in his last six holes, he admitted that despite suggestions the west course was easier, he felt otherwise.
Maritz said: 'That's what everybody thinks (the west course is easier) but over the last few years, I think I've played better on the east course.
'I think it's because in junior days and amateur days we played a lot of tournaments on that course. I think if I can shoot anything close to that tomorrow, I'll be very, very happy.'
The Pretoria-born golfer, now based in Tulsa, Oklahoma where he had taken up a club pro role in his time away, added: 'I've been working really hard on my short game, it's not my strong point, so I'm just ecstatic, it's just a magical round for me today and I'm over the moon.'
Countryman Grace, the clubhouse leader for most of the day, recorded six birdies and an eagle in a perfect round, and conceded that the west course players had no option but to score low today.
'I thought beforehand that one of the keys was to go low on the west and fortunately I managed to do it today,' he said.
'I played really well, I didn't make any mistakes out there and everything went to plan, so I'm pretty pleased with that.'
Defending champion Charl Schwartzel had a solid, yet unspectacular, start to his tournament with a 68 on the east course, while one of his playing partners, Northern Irishman Darren Clarke, ended on one under 70 thanks to three successive birdies to finish.
The other Irish players in the field are also under par after the opening round.
Colm Moriarty is four under after his 67, while Gareth Maybin is two under after shooting 69.