The four are among the eight players in action next week as they bid to end the year by winning the prestigious season-ending tournament in Singapore.
Ivanovic posted the picture above on her Instagram account and wrote: “Selfie time! @petra.kvitova @aradwanska @carowozniacki”
Wozniacki then enjoyed dinner with world No1 Serena Williams ahead of the season finale, which gets under way on 20 October.
The Dane posted the picture below on Instagram and wrote: “Dinner with @serenawilliams in Singapore.”
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