Two-time champion Victoria Azarenka withdraws from Australian Open
Former world No. 1 Victoria Azarenka played only six matches in 2017, and her year-ending ranking plummeted to No. 208. AP

MELBOURNE, Australia — Two-time champion Victoria Azarenka has withdrawn from the Australian Open, with her wild-card entry reallocated to Ajla Tomljanovic of Croatia.

Open organizers announced Azarenka's withdrawal in a social media post on Monday, a week before the tournament begins.

"It's unfortunate that (Azarenka) is unable to travel to Australia," organizers posted on Twitter, quoting tournament director Craig Tiley. The Australian Open, "is her favorite tournament and she's looking forward to returning to Melbourne next year."

Azarenka, who won the Australian Open in 2012 and 2013, has been involved in a custody dispute involving her son Leo, who was born in 2016.

She hasn't competed anywhere since Wimbledon, where she lost in the fourth round on July 10.

Former No. 1-ranked Azarenka played only six matches in 2017, and her year-ending ranking plummeted to No. 208.

Australian Open organizers last month granted her a wild card, with Tiley saying at the time: "Vika's current situation is obviously very difficult for her and we have reached out to offer any support we can."

Azarenka was initially scheduled to make a return to competitive tennis in New Zealand last week, but withdrew from that tournament as well.

The Australian Open starts next Monday at Melbourne Park.

Defending champion Serena Williams has already withdrawn, saying her game wasn't back to a level where she believed she could contend for the title just four months after giving birth to her first child.

Tomljanovic will play in the Australian Open main draw a fourth time. Her best result is the second round.

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