SYDNEY, Australia—The participation of Novak Djokovic, men’s tennis World No. 1, in the Australian Open could be decided Sunday afternoon, a panel of three federal judges have said as they adjourned to decide whether to reinstate Djokovic’s Australian visa after almost five hours of hearing arguments. Chief Justice James Allsop said that the court hoped to deliver a result as early as Sunday afternoon but possibly as late as Monday morning. The world’s No.1 is slated to play in the first round of the grand slam on Monday. Djokovic brought the legal challenge after Australia’s Immigration Minister Alex Hawke revoked his visa on Friday afternoon on the grounds that his presence in Australia may foster anti-vaccination sentiment and an increase of “civil unrest” that could escalate into super spreader events amid the nation’s surge in COVID-19 cases. Allsop asked the minister to explain the government’s position on the “counter-factual,” referring to the …