Furyk had been in second place after the first round

R2 LEADERBOARD:
GB/Ire unless stated
-10 J Furyk (US)
-6 H Stenson (Swe)
-5 E Els, C Schwartzel (both SA)
Selected others:
-2 D Howell
level J-M Olazabal (Sp)
+8 C Montgomerie

Jim Furyk hit a six-under-par 66 to go four shots clear of first-round leader Henrik Stenson at the storm-hit Nedbank Challenge in Sun City.

Furyk, a shot behind after the first round, even overcame a thunderstorm delay to set the pace on 10 under.

South African duo Ernie Els and Charl Schwartzel share third on five-under.

David Howell, the sole English player in the tournament, is well off the pace and Colin Montgomerie is last on eight over after a second round of 77.

The thunderstorm suspended play for two-and-a-half hours with five holes remaining for the leading pair, but the delay failed to break Furyk's rhythm.

Stenson could only manage a 71 after virtually cancelling out his three birdies with two bogeys, while Furyk took full advantage with his second straight bogey-free round.

European Order of Merit winner Padraig Harrison of Ireland held a share of third until a final-hole bogey saw him drop to a tie for fifth.

Montgomerie, bottom of the leaderboard after a first-round 75, made a quintuple bogey after hitting the trees three times at the par-four 11th and ended up eight over.