World number two Ons Jabeur suffered a shock quarter-final exit from the Jasmin Open on home soil in the Tunisian city Monastir on Friday.
The 28-year-old was beaten 6-3, 4-6, 6-4 by American Claire Liu, who is 73rd in the world rankings, in a rare home appearance.
Jabeur finished as runner-up at Wimbledon and the US Open this year, while also winning two tour titles, in Madrid and Berlin.
Her early exit is a blow for organisers of the tournament in Monastir, with the city on the central coast of Tunisia being the first in the country to host a WTA tour event.
The top seed at the tournament, Jabeur had beaten Ann Li and Evgeniya Rodina in straight sets to make the last eight.
The local hero was born 10 miles from Monastir, in Ksar Hellal, and reached her first ITF final in the city as a 15-year-old in 2009.
She will now focus on her first WTA Finals, which begin in Fort Worth on 31 October.
Only one other WTA event was held in Africa this year - another WTA250 tournament, in Morocco in May - with the Jasmin Open ending on Sunday.