JOHANNESBURG -- Henrik Stenson opened up a four-shot lead at the South African Open with a second-round 65 on Friday before play was suspended for the day because of an electrical storm.
Stenson's 7-under 65 to go with his opening 66 put him 13 under par and well clear of Swedish compatriot Magnus Carlsson, who shot a 67 to move to second on 9 under. Further back, a large number of the field had yet to finish.
First-round leader Merrick Bremner of South Africa was also at 9 under but still had four holes to play when they were called in for lightning at the Serengeti Golf and Wildlife Estate on the edge of Johannesburg.
Seeking a first tournament win in three years -- and first on the European Tour in five years -- Stenson had five birdies, an eagle and no bogeys to take control, giving him a good chance of staying inside the top 60 players in the European money list and making the end-of-season DP World Championship next week in Dubai.
Charl Schwartzel was in a tie for eighth at 6 under with four holes to finish in his round. The former Masters champion picked up three birdies, but also had two bogeys to make little progress on the leaders. Former top-ranked Martin Kaymer was 4 under, also with four to play, and nine shots off Stenson's clubhouse lead.
Having eagled the par-4 17th on Thursday, Henson made use of another booming drive Friday to set up an eagle 3 on the 576-yard par-5 eighth, his penultimate hole. Starting on No. 10, the Swede had parred his first five holes before a run of three straight birdies just before the turn.
"I've hit probably more drives in the past two days than I have all season," he said. "The way I played I had plenty of chances and I could have been three or four shots better. But ... I'm not going to be complaining about 13 under."
Behind him, countryman Carlsson was well-set for a weekend challenge after six birdies and a single dropped shot put him on 135.
Bremner couldn't match the precision of his course record-equaling opening-round 64, dropping shots with a bogey and double bogey to go with four birdies so far in his incomplete second round.
Lloyd Saltman of Scotland was alone in fourth on 8 under after a 66, one ahead of two players in a tie for fifth: South African Oliver Bekker (69) and a third Swede, Michael Jonzon (69).
South African Open debutant Matthew Carvell was also 7 under but had only finished half his second round when a typical Highveld summer storm arrived on the eastern outskirts of Johannesburg in the mid-afternoon.