England's David Lynn, with only one win in over 300 European Tour starts, set the clubhouse target during the second round of the Joburg Open.
The 36 year old from Stoke added a second round 67 to his opening 63 at Royal Johannesburg and Kensington to be 12 under par at halfway.
Two behind and with three holes still remaining were playing partners Darren Clarke and Charl Schwartzel, both of whom continued to make good progress over the longer East Course.
Like Lynn, they went round the shorter West Course in eight under on Thursday to be only one behind surprise pacesetter Neil Schietekat, but the South African could add only a 72 on the resumption and slipped back to eight under.
Lynn's only victory came in the Netherlands in 2004. He has had no fewer than 23 top ten finishes since then.
After turning in 34 he added further birdies on the 11th and 18th to relegate fellow Englishman Danny Willett and South Africans Jbe’ Kruger and Hendrik Buhrmann to joint second spot on ten under.
Earlier Michiel Bothma made a hole in one on the 13th of the West course with an eight iron tee shot – and it was likely to prove crucial. It led to a one under 70 for a two under total, which looked likely to make the cut by a single stroke.
Clarke and Schwartzel were approaching the 17th green when play was suspended in mid-afternoon for the second day running because of a thunderstorm.