South Africa's Louis Oosthuizen produced a nine-under-par 64 to open up a two-shot lead over Welshman Rhys Davies after the third round of the Hassan Trophy in Morocco.
Oosthuizen carded 10 birdies and one bogey on the Red course to move on to 20 under par for the tournament.
Davies, the halfway leader after an eight-under 64 on the par-72 Blue course on Friday, shot a 68 on the Red to sit two clear of France's Thomas Levet and another South African, Thomas Aiken.
The 24-year-old Welshman, a team-mate of Rory McIlroy at the 2007 Walker Cup and third in the Malaysian Open two weeks ago, picked up three shots on the back nine after four birdies and two bogeys on the front nine to keep himself firmly in contention going into the final round.
Levet also went round in 68 on Saturday, with Aiken shooting a 67.
Spain's Ignacio Garrido was one stroke further back following a 69, while England's Danny Willett shot up the leaderboard thanks to a 64, including four birdies in four holes from 13 to 16.
That put Willett on 14 under, one shot ahead of fellow countryman Robert Rock, who carded a 67.
Nick Dougherty, the first-round leader, could only manage a 72, though, to sit on 11 under, nine off the pace.
20 March, 2010