World No. 1 Iga Swiatek suffered an unexpected defeat in the semifinals of the women's WTA Finals being held in the US.
The 21-year-old Polish tennis star faced world No. 7 Aryna Sabalenka (Belarus), who won in three sets. The match lasted 2 hours and 9 minutes.
Sabalenka's opponent in the final will be Caroline Garcia (France). The world No. 6 had defeated world No. 5 Maria Sakkari (Greece) in their semifinal clash.
The final of the WTA Finals will be played Tuesday.
The prize fund of the tennis tournament is $5 million.