Kapur, who was on the cut-line at one-under, when play stopped due to darkness last evening, birdied the 12th, 15th and 18th to compile a five-under 65 in second round for a total of four-under 136.
In the second round, Kapur had three birdies on third, seventh and eighth and a bogey on ninth and then added birdies on 12th, 15th and 18th.
Campillo and South African Colin Nel both broke the magic 60 barrier within moments of each other although they will not enter the record books as preferred lies were allowed on Mount Edgecombe's saturated fairways.
Spain's Campillo had two eagles and seven birdies in his incredible round to reach 11-under for the tournament, but first round leader Brooks at 14-under following a second round 64.
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England's Matthew Baldwin shot a 62 to lie tied second with Campillo and Dawie van der Walt on 11-under. Home favourites Branden Grace and Oliver Bekker are on 10-under.
World Number 49 Grace won four times on The Race to Dubai in 2012, but having had several near misses in a trophy-less 2013 is keen to return to wining ways.
Grace can also cement his place in the Official World Golf Ranking's top 50 who will receive invites to the Masters Tournament at the end of the year, but the Pretoria golfer has another motive.