Former Open champion Paul Lawrie fired a three-under 69 to take the halfway lead in the Nedbank Golf Challenge in South Africa.
Lawrie heads the elite 12-man by a shot on four-under after he and second-placed Martin Kaymer (69) shot the first sub-70 rounds of the week on the tough par 72 at the Gary Player Country Club in Sun City.
Scot Lawrie birdied five, 12 and 14 to move to four-under before suffering his only blemish of the day at 15. However, he birdied 17 after a superb approach and got up and down at 18 to secure the 36-hole lead.
Kaymer was quick out of the blocks with birdies at two, four and seven and he repaired the damage of bogeys at eight and nine with birdies on the two back nine par fives (10 and 14) to finish at three-under.
It's then two shots back to South African duo Charl Schwartzel and Louis Oosthuizen along with Italian Francesco Molinari and American Bill Haas.
Oosthuizen battled stomach cramps all day and looked to be running out of gas when he double-bogeyed 17 but the 2010 Open champion hit back with a fine birdie at the last.
Lee Westwood, the winner here for the last two years, also birdied 18 but that was for a 73 after a round which included double bogeys on five and 17. The Englishman will go into the weekend four shots back.
Joint first-round leader Nicolas Colsaerts slid down to four-over after carding back-to-back sevens at the second and third.
However, his 78 wasn't the worst round of a tough day in which the field were a collective 12-over. That unfortunate fate fell to world number four Justin Rose, who had a triple, four bogeys and not a single birdie in a seven-under 79 which left him at eight-over and last by four shots.
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