Germany's Marcel Siem extended his Trophee Hassan II lead to four shots on Saturday as a third round 69 also kept alive his hopes of making a maiden Masters appearance.
The 32-year-old Siem, who needs to win on Sunday to climb into the world's top 50 and earn a ticket to Augusta, finished the day on 15 under par, a round boosted by four birdies in six holes around the turn at the Golf du Palais Royal.
Spain's Pablo Larrazabal, 2011 champion David Horsey of England and Finland's Mikko Ilonen are all grouped in second place.
After Siem had bogeyed the first, Horsey and Ilonen joined the German in a share of the lead.
But once the leader had hit two long birdie putts at the seventh and ninth to turn one ahead, his rivals struggled to stay in touch.
Siem extended his lead with a birdie at the long tenth before striking his tee shot to within a foot of the 12th pin.