Murless is seeking to claim his first victory in more than five years after winning the Platinum Classic in 1996. He opened with an 8-under-par 65 and holds a one-shot advantage over compatriot Rudi Whitfield.
His nine birdies were marred only by one bogey at the third hole.
'I am happy with my round, although the bogey at 3 was frustrating,' said a delighted Murless after his round.
'I hooked my tee shot into the trees on the left and tried to play a fancy shot out, only to hit a tree on the way. I was lucky the ball spun into the fairway off the tree. I hit a sandwedge to the green and then missed about four foot putt for par.'
The 25-year-old birdied every second hole from the par-4 fifth to the par-3 16th, where he added an eighth and finished with his ninth birdie of the day on the final hole.
Murless has been experiencing a return to form lately with solid
performances toward the end of the summer tour. He finished joint eventh in the Nashua Masters and joint eighth in The Tour Championship.
'My fiancee, Joanne Uys, sat me down for a good talk just before the Nashua Masters,' explained Murless.
'She reminded me of the reasons why I started playing this game. Basically, I had forgotten to have fun out there. Instead, I was
obsessing all the time about problems around my game. I didn't enjoy
playing anymore and hated the travelling.
'Since we are getting married on the 30th of March, I'd better start making some money to support her!' he joked.
Whitfield also stumbled at the third for his only bogey of the day, but recovered well for a run of birdies that started on the fourth and continued through Nos. 6, 8, 13, 14, 15, 17 and 18.
Murless's nearest challengers are Whitfield at 7-under and a group of four on 6-under-par, including Craig Cowper and Denny Lucas from England and South Africans Hennie Otto and Andre Cruse.
The highlight of the day belonged to Cruse, who celebrated the anniversary the hole-in-one prize he won in last year's tournament with another today.
The South African hit a 6-iron from 170 yards into the wind on the 16th tee straight into the hole.
'I am shocked. We were all so shocked!', said a delighted Cruse after his round. 'Last year Ulrich van den Berg and I were 'hi-fiving' each other, but today we just looked at each other in utter disbelief!'
Almost one year since he left with a Nissan Terrano 4 X 4 after holing the par-3 11th, Cruse will drive from Lusaka, but this time in a Toyota worth approximately $15,000.
Simon Hurd and Gary Birch Jr. of England, Germany's Kariem Baraka and South Africans Titch Moore, Thabang Simon, Brett Liddle and Michiel Bothma are all at 5-under par 65.
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