Caroline Wozniacki has suffered a third-round defeat to Spanish world number 73 Garbine Muguruza at the Miami Masters.
Ninth seed Wozniacki was brushed aside 6-2 in the opening set before her opponent wrapped up the victory 6-4.
The former world number one was beaten in the semi-finals of last year's tournament in Florida.
Muguruza will meet Li Na in round four following the fifth seed's straight-sets triumph over Varvara Lepchenko.