Play was stopped for several hours due to lightning and called for the day with much of the field still on the course. Those players included two-time defending champion Charl Schwartzel, who was even-par after 15 holes when play stopped.
Elson and McGrane are one stroke ahead of Desvonde Botes, Peter Karmis and Reinier Saxton. Another six golfers are at 6-under and 10 more at are 5-under.
Botes and Robert Rock, who has three holes of his first round to complete, are the only players among the top 22 to open play at the par-72 East Course at the Royal Johannesburg and Kensington Golf Club. The rest played the relatively easier par-71 West Course.
McGrane was among the first players on the course Thursday. He was 1-under after four holes and had birdies on six of his next eight holes. He got to 9-under on the day with an eagle at the par-5, 539-yard 15th hole. He finished with a bogey, however.
Elson opened his round with four straight birdies and made the turn at 6-under. Back-to-back bogeys at Nos. 10 and 11 dragged him back but he finished strong with four birdies in his final six holes. It was a birdie at the par-4 18th that earned him the tie with McGrane.
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