A windswept Pezula Championship Course gave little away on the first day at the inaugural Vodacom Origins of Golf Tour event, with only Terblanche and five others completing their rounds in par or better.
Grant Muller was the only other player under par, his 1-under 70 good enough for second place on his own. Early clubhouse leader Dijon Tintinger, Ian Hutchings and Jaco van Zyl are third at even par.
Terblanches round was kick-started by a superb eagle-2 on the 10th hole, where a 407-yard drive landed on the green and came to rest 10 feet from the flag. Three further birdies saw Terblanche make the turn in four-under 32, before his round, like the wind, changed direction almost instantly.
Terblanche played the first six holes of his inward half in 5 over, but he fought back in the fading light to repair some of the damage with three successive birdies to finish his round.
Second placed Muller also was also quick to get out of the blocks, reaching the par-3 15th (his sixth) in 3 under after holing his 113-yard approach shot for an eagle-2 on the signature 14th hole.
Muller said he might have been level with Terblanche were it not for an agonizing miss on the following hole, what he called a massive horse-shoe lip-out for birdie.
A triple-bogey-7 on the 16th ensued after Muller drove out of bounds, but two birdies to finish his opening nine and an even par inward half combined to see Muller home comfortably.
The hero of the morning session, arguably more difficult with winds dropping off ever so slightly later in the day, was Tintinger and Tintinger alone.
Tintinger, who is currently being coached by Ashley Roestoff at Roodepoort Golf Club in Johannesburg, led by five shots by the end of the morning session.
Obviously, Im happy with my round, but I still feel as though I left some out there, said Tintinger.
The wind was surprisingly strong this morning, so it was a matter of just keeping it in play and trusting your swing ' getting up there and just hitting it.'
Tintinger used his share of luck, too. An errant drive on the par-5 13th hole looked destined for the fynbos before a cart path came to the rescue.
I just wanted to drive it down there and in play, but it pitched on a cart path and finished 80 meters from the green, said Tintinger. I made a birdie there and that started my round.
Vodacom provided an old-fashioned atmosphere with amateurs wearing plus fours and vintage cars decorating the practice green. But while amateurs were dressed like the legends of golf most of them had trouble emulating the scores with the wind sweeping across an already testing golf course.
This is the fist of five Vodacom Origins of Golf Tour events, an initiative from the cellular giant that will conclude in a grand final down the road at Fancourt at the end of October.