PERTH, Australia (AP) -- Two-time Wimbledon champion Petra Kvitova and Olympic gold medalist Jack Sock are the latest players confirmed to compete at the Hopman Cup in January, one of the key warm-up events for the Australian Open.
They'll join Roger Federer, who earlier this summer announced he would play in the exhibition event for the first time in 15 years.
Kvitova, who helped lead the Czech Republic to victory in the 2012 Hopman Cup, will partner with Adam Pavlasek for the Czech team, while Sock will represent the United States alongside Coco Vandeweghe, making her debut in the mixed-team event.
The Czech and American teams were announced Monday, along with the other teams to take part in the 2017 event: Australia, Britain, France, Spain and Germany. The players for those teams have yet to be decided.
Federer, who decided to sit out the rest of this season following his loss in the Wimbledon semifinals to protect his surgically repaired left knee, will play for Switzerland with partner Belinda Bencic. He teamed with Martina Hingis to win the event in 2001, then played the following year with his now-wife Mirka Federer.
Australia's Nick Kyrgios and Daria Gavrilova are the defending champions, beating Ukraine in the final in January.