Second seed Timea Bacsinszky was the biggest casualty of the second round of the Grand Prix De SAR La Princesse Lalla Meryem as teenager CiCi Bellis staged a fightback to claim a second-round win.
Bellis displayed her potential at the Dubai Duty Free Tennis Championships with a run to the quarter-finals, where she lost to Caroline Wozniacki, and is in to the last eight in Rabat after saving a match point to beat Bacsinszky 6-7 (3-7) 7-5 7-5.
The 18-year-old American will now face compatriot Varvara Lepchenko after she also came from behind to defeat fifth seed Yulia Putintseva 1-6 6-4 6-1.
Eighth seed Alison Riske is also out after a 7-6 (9-7) 6-7 (4-7) 6-2 loss to Sara Errani. Next up for Errani is third seed Daria Gavrilova - a 6-2 6-1 victor over Elise Mertens.
Top seed Anastasia Pavlyuchenkova beat Ekaterina Makarova 6-2 7-5, setting up a quarter-final with seventh seed Lauren Davis after her easy 6-1 6-2 triumph versus Kateryna Bondarenko.
Elsewhere in the draw there were wins for Tatjana Maria and Francesca Schiavone.