Grace takes charge at Fancourt as Harrington suffers another day to forget
The lead is still four shots after two rounds of the Volvo Golf Champions at Fancourt in South Africa – but now it is local man Branden Grace rather than Belgian Nicolas Colsaerts out in front.
Grace, last man into the European Tour's winners-only event thanks to his victory at the Joburg Open last Sunday, shot 66 to reach 12 under par.
Colsaerts, on the other hand, had a 76 – 12 more than his course record first round – to drop to joint fifth place.
While that was the joint worst score of the day, the best was a 65 from England's Lee Slattery. And it not only lifted the 33-year-old from 22nd to joint second with Thomas Aiken, another of the home contingent, but also earned him a 25,000 car.
Leading the way: Branden Grace plays a sweet shot at the 18th to finish his day on a high
Playing partner Retief Goosen (68) received the same prize as they combined with English amateur Mark Vandenberghe to win the one-round team event.
Jose Maria Olazabal almost joined them in winning a car, lipping out for a hole-in-one at the short 17th, but Europe's Ryder Cup captain – at 596th in the world the lowest-ranked player in the 35-strong field – was happy enough with a 68 to be in fourth spot on his own.
Water under the bridge: Padraig Harrington was in cheerful mood despite another woeful day on the course
For the second day running, though, Padraig Harrington finished with a double-bogey seven and, having also dropped shots on the previous two holes, the Dubliner's 73 left him with eight shots to make up like Open champion Darren Clarke (68) and England's Tom Lewis (74).
Only last month 23-year-old Grace was at the Tour qualifying school in Spain, but he came through that six-day ordeal in joint 10th place and has been flying ever since.
'I'm just really enjoying it out there,' he said after grabbing eight birdies.
'It's probably my favourite course in the world and coming back here is a fabulous feeling, especially playing well.'
Take a break: Darren Clarke and Charl Schwartzel plan their putts
Slattery feared he would be at the Tour school as well – in his case for the ninth time – until he won the Madrid Masters in October.
'Winning certainly gives you belief,' said the 33-year-old from Southport after picking up an amazing 10 birdies just as Colsaerts had done in the opening round.
'That's probably my best round out there, one I'm going to remember for the rest of my life.
'Because of the team prize I was willing Retief's putts in as well. God knows what the amateur felt like, but he handled it well.
'I've had about 12 holes-in-one, but have never won a car before. I still might take the money instead, though.'
Digging in deep: Colin Montgomerie misses a putt at the eighth
Olazabal insists that even if he grabs his first victory for seven years on Sunday it will not change his view about September's match in Chicago.
'I've made that point very clear – there is no way,' said the 45-year-old Spaniard.
'Even if I make the Ryder Cup (team) I will not play. I've answered that question.'
Aiken has an added reason for wanting to come out on top – he is on a campaign to help save the rhino and the more publicity he can get the better.
'I've started my own charity,' he said.
'It's disgusting what's happening. We've got a war going on basically with the east.
'Rhino horns are being valued a million dollars. We've got tractors on the grounds, roadblocks and help from the Air Force because they are shooting them from helicopters now.
'We've got about six years left until they are extinct and if we hang around too long we are going to be too late.'
Colin Montgomerie had been hoping to improve on his opening 70, but instead shot 75 and so will go into the third round only joint 24th – 11 strokes behind.