Sydney: Defending champion Petra Kvitova and second seed Agnieszka Radwanska are the latest stars to have troubled build-ups to this month's Australian Open after pulling out of the Sydney International yesterday.
Poland's Agnieszka Radwanska (left) kisses Petra Kvitova of Czech Republic after beating her in the WTA final at Singapore last November. Pic/Getty Images
Third-seeded Czech Kvitova will not be able to defend her Sydney title after succumbing to a gastrointestinal illness, which plagued her in China last week.
Poland's Radwanska joined Kvitova after withdrawing from the Sydney tournament with a left leg injury.
Their withdrawals from the final lead-up tournament to the year's first Grand Slam event came after injury problems at other Australian tournaments for the world's top-four ranked stars Serena Williams (knee), Simona Halep (Achilles), Garbine Muguruza (foot) and Maria Sharapova (forearm).
"I'm really disappointed to have to withdraw but unfortunately I am still not feeling well," Kvitova said.
It is the second consecutive event from which the World No 6 has withdrawn in the new year.
She retired with a stomach virus during the Shenzhen Open in China last week. Radwanska said she needed to rest her leg after playing five matches in the past week.