Naomi Osaka via personal IG for Tag Heurer.

Naomi Osaka, currently ranked No. 13 in WTA rankings, is on track to return to playing professional tennis. The four-times Grand Slam champion Osaka returned to the practice court in early November, after leaving the US Open with the announcement that she needed to step away from the game. Osaka also took a two-month mental health break before the Open.

As of Christmas, Naomi Osaka is scheduled to return to professional tennis at the Melbourne Summer Set, the first week of 2022. Melbourne is a warm-up tournament for the Australian Open, playing January 17-30. Osaka defeated Jennifer Brady in the 2021 Open — her second Melbourne trophy — and is a narrow favorite to win in January 2022, with Brady ranked No. 2.

Emma Raducanu, bringing momentum from her shocking US Open victory in September, is ranked third to win in Australia. Tennis great Serena Williams has confirmed that she will not be playing in Australia.

"While this is never an easy decision to make, I am not where I need to be physically to compete," Williams said in confirming her not playing the Open. "Melbourne is one of my favorite cities to visit and I look forward to playing at the AO every year. I will miss seeing the fans, but am excited to return and compete at my highest level."

The Australian Open 2021 was delayed due to COVID and eventually took place February 8 to 21. Omicron has exploded in Australia in recent days — although Delta continues to hospitalize more Aussies. Almost 20 percent of Christmas Eve flights were cancelled today, writes Reuters.