Local hope Alex de Minaur withdrew from the Australian Open due to an abdominal injury.
De Minaur helped Australia into the ATP Cup semi-finals earlier this month, including pushing Rafael Nadal in the last-four loss to Spain.
But the 20-year-old will now miss the year's opening grand slam, where he reached the third round in 2019.
"Unfortunately Australian No.1 @alexdeminaur has withdrawn from #AusOpen 2020 with an abdominal injury," the tournament wrote on Twitter.
World number 21 De Minaur enjoyed a stellar 2019 with a 41-20 win-loss record and three titles.