SYDNEY, Dec 10 (Reuters) - World number one Ash Barty will kick off her 2022 season at the Adelaide International Australian Open warm-up in the first week of January, tournament organisers said on Friday. The Wimbledon champion, who won the tournament in its inaugural year in 2020, last played competitively at the U.S. Open in early September before returning home to Australia. Barty, who was named WTA Player of the Year this week after winning five titles in 2021, will be joined at Memorial Drive by defending champion Iga Swiatek and former world number ones Garbine Muguruza and Karolina Pliskova. Australian Open champion Naomi Osaka and U.S. Open winner Emma Raducanu will headline the two women"s warm-up tournaments taking place over two weeks at Melbourne Park, which have been dubbed the "Melbourne Summer Set". Osaka, now ranked 13th in the world, also cut short her 2021 season after her exit from the U.S. Open in a year when she withdrew from the French Open and skipped Wimbledon citing mental health issues. British teenager Raducanu will use the tournament to acclimatise to Australian conditions on her first visit to Melbourne Park as she looks to build on her sensational run to the title at Flushing Meadows. World number two Aryna Sabalenka and last year"s U.S. Open runner up Leylah Fernandez will also play in Adelaide, which will host nine out of the top 10 players in the women"s world rankings. Rafa Nadal, who has decided not to take part in the ATP Cup in Sydney in the first week of the year, headlines the ATP 250 tournament in Melbourne from Jan. 4-9, while Gael Monfils will be the big draw in the men"s tournament in Adelaide. World number one Novak Djokovic was listed as part of the Serbia team for the ATP Cup but his involvement in the Australian tennis season remains uncertain because of the vaccination requirements. Roger Federer, who shares the record of 20 Grand Slam titles with Djokovic and Nadal, has already confirmed that he will not be travelling to Australia as he recovers from knee surgeries.