Romania's Simona Halep missed out on a chance to become the new world number one after being thrashed by Garbine Muguruza in the Cincinnati Open final.
Halep, 25, lost to the Wimbledon champion 6-1 6-0 in just 57 minutes.
A win would have seen world number two Halep replace Karolina Pliskova at the top of the rankings.
Britain's Jamie Murray and Brazilian Bruno Soares lost their men's doubles final to the French fifth seeds Nicolas Mahut and Pierre-Hugues Herbert.
Murray and Soares were beaten 7-6 (8-6) 6-4 in one hour and 37 minutes.