The COVID-19 pandemic has seen big-serving American John Isner become the latest star to withdraw from the Australian Open.
The first grand slam of 2021 has already been stripped of arguably its biggest name after Roger Federer confirmed in December that he would not be participating in the Melbourne Park major.
‘CAN’T GO AHEAD’: Australian Open hit by shock virus news
Now former top 10 star Isner has joined Federer in pulling out of the tournament, citing family reasons and the coronavirus crisis.
Isner announced his decision on Monday night in the United States after losing to fellow American Sebastian Korda in the quarterfinals of the Delray Beach Open.
The 35-year-old American has two young children and said he wanted his family to travel together to "make it as much fun as possible on the road ... because I won't be playing tennis forever."
He said that scenario is not possible because of the virus and that travelling to Australia this year would have meant too much time away from his family.
Isner, now ranked 25th in the world, lost to Korda 6-4 4-6 6-3.
— Tennis TV (@TennisTV) January 12, 2021
The 20-year-old Korda is a former World No. 1 junior who achieved a career-high ranking of No. 116 last autumn.
His father, 1998 Australian Open champion Petr Korda, played at Delray Beach twice but never advanced beyond the second round.
Harrison beat Gianluca Mager of Italy 7-6 (2), 6-4, and his opponent Tuesday will be No. 4-seeded Hubert Hurkacz of Poland, who swept qualifier Roberto Quiroz of Ecuador 6-4, 6-4.
The 26-year-old Harrison's career has been slowed by injuries that required surgery eight times, and he came into the tournament ranked No. 789.
He has five ATP Tour match victories, with three of them coming in the past week. He also won two matches in qualifying.
"It feels pretty amazing," Harrison said.
"I'm pretty even-keeled right now - just happy to keep playing."
Isner's withdrawal comes amid a threat of sanctions for players if they breach stringent virus protocols when they arrive this week for the Australian Open.
The calendar's first Grand Slam normally starts in the third week of January but planning for this year's tournament has been a logistical nightmare for beleaguered organisers.
Tennis Australia initially wanted players arriving in Melbourne by mid-December.
Strict virus measures for Aus Open stars
But restrictions on international arrivals to the state of Victoria pushed back the tournament start date to February 8, with a series of WTA and ATP events being played at Melbourne the week before to ensure players are up to speed.
Melbourne was the epicentre of Australia's largest second wave outbreak of coronavirus, which prompted strict lockdown measures for four months.
This grim backdrop fuelled tense negotiations between government officials, organisers and players to iron out an agreeable health security protocol for the Australian Open.
The sticking point had been over allowing players to practise during the compulsory 14-day quarantine period but eventually authorities gave the green light and granted daily five-hour blocks for training and treatment.
Players, however, face stricter measures compared to last year's US and French Opens held in cities stricken by the virus and will be required to spend 19 hours daily during quarantine confined to their hotel rooms.
Defending Australian Open champion Sofia Kenin admitted it was "not the most ideal situation". "It is what it is. The rules are quite harsh, but it's for everyone," she said.
There is also the threat of sanctions, including hefty fines, spending additional time in quarantine or deportation, if the rules are broken.
Ukrainian world number five Elina Svitolina hired a mental coach in an effort to cope with the stress and uncertainty.
"I think during the difficult time right now, mentally it's very important to stay strong, to stay fresh," she said.
Six-time Australian Open champion Federer's decision to withdraw affects the pulling power of the tournament, which was left reeling after suggestions he skipped because of the quarantine rules.
The 39-year-old had two rounds of knee surgery last year and has not played since his semi-final defeat to Novak Djokovic at the Australian Open 12 months ago.
"The problem is that Mirka (Federer's wife) and their children couldn't leave the room," Tennis Australia's head of player liaisons Andre Sa told Brazilian media.
"They would have to stay 14 days in the room. The exception is only for players."
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