Stosur lost 6-2, 6-2 to 10th seed Anastasia Pavlyuchenkova in round two and said she had "done more than I ever thought was possible".
The world number one from Serbia, who desperately wanted to defend his crown, flew out hours before the Grand Slam after his last-gasp court bid to stay in Australia without being vaccinated against Covid failed.
The Greek star lost his first singles match since going under the knife in late November, losing to Argentina's world number 11 Diego Schwartzman 6-7 (5/7) 6-3, 6-3 on Monday night.
The already-delayed opening Grand Slam of the year was plunged into yet more chaos last week when Australia's second most populous city was ordered behind closed doors after a new COVID-19 cluster.
Snap restrictions were ordered last Friday after a small outbreak of the more infectious UK COVID-19 variant.
Preparations for the year's opening tennis Grand Slam were thrown into disarray when a worker at one of the designated tournament hotels became infected with the virus.
All competition at six tournaments scheduled for Thursday was called off overnight and 520 people who flew to Melbourne for the Australian Open were ordered to isolate in their accommodation and get tested
Victoria state's Sports Minister Martin Pakula said it equated to some 390,000 spectators across the two-week spectacle – around half the attendance of last year.
Players are expected to arrive in Melbourne from mid-January, undertaking a mandatory two-week quarantine period that permits them to train for a maximum of five hours per day at Melbourne Park
Australia’s Victorian state Premier Daniel Andrews said despite “incredibly complex” negotiations, he is confident January’s Australian Open tennis tournament will proceed.
The new arrangements will involve players flying into Melbourne to undergo two weeks of mandatory quarantine, when they will be restricted to hotels but have access to tennis courts.
Australian Open champion Sofia Kenin says she is frustrated by her inability to rediscover the rhythm she had at Melbourne Park after crashing out of the Qatar Open
Tennis Australia (TA) invited Court, who won a record 24 Grand Slam titles, to Melbourne Park to recognise the 50th anniversary of her 1970 calendar Grand Slam, while saying it disagreed with her “personal views”.
Australian Open 2020: Novak Djokovic advises Dominic Thiem, Alexander Zverev to stay patient in pursuit of glory
Novak Djokovic will meet either Alexander Zverev or Dominic Thiem in his bid for a record-extending eighth Australian Open title and on Thursday he advised his younger challengers to be patient in their pursuit of glory.
Australian Open 2020: Roger Federer happy with semi-final run, believes he has one more Grand Slam triumph left
Federer, who suffered a groin problem in the quarter-final against Tennys Sandgren, bowed out of Melbourne Park after a comprehensive 7-6(1) 6-4 6-3 defeat to the defending champion Serb.
Australian Open 2020: Novak Djokovic extends Grand Slam streak against Roger Federer to enter 8th final at Melbourne Park
Casting aside a bit of a poor start during the rivals' 50th meeting, Djokovic stretched his Grand Slam winning streak against Federer to six in a row with a 7-6 (1), 6-4, 6-3 victory Thursday night
Australian Open 2020: Rafael Nadal heaps praise on Dominic Thiem after loss to Austrian in quarter-finals
Thiem ended Nadal’s bid to match Roger Federer’s record of 20 Grand Slam titles, at least for now, having ridden his luck at times in claiming the three tiebreaks.
Australian Open 2020: Nick Kyrgios wins thriller, sets up showdown with Rafael Nadal; Karolina Pliskova among women's top seeds knocked out in straight sets
Nick Kyrgios put aside a bloody hand, a hamstring issue, a tiff with the chair umpire and a resilient opponent who saved a pair of match points.
Australian Open 2020: With stunning upsets and epic tennis, drama-filled Friday gives fans action worth every penny
The Australian Open produced a crazy, drama-filled day today at Melbourne Park, with fans witnessing epic matches, upsets, and just some great tennis, in general.
Australian Open 2020: Serena Williams secures berth in third round; Coco Gauff to meet Naomi Osaka after three-set win
Checkout all the match results of the Women's Singles fixtures from the third day of the Australian Open 2020