Els, who had started his round at the 10th, played his last five holes in three under with a birdie at the par-four fifth, another one at the tricky par-three sixth, and an eagle three at the long seventh.
Britain's Graeme McDowell, who moved up to 14th after a third-round 67, had a remarkable outward nine, with four bogeys and two birdies, and also took five at the par-three 16th to finish with a 76 for a share of 32nd.