Aussie runner Jessica Hull has been forced out of the world championships in Oregon after testing positive for Covid-19.
The leading middle-distance runner was due to take part in the women's 5000m but has been forced out of the event after the devastating news.
Hull has gone into isolation for five days, having returned the positive test following her seventh-placed finish in the 1500m final on Monday.
She is the first member of the 64-strong Australian team in Eugene to test positive to Covid-19 during the 10-day championships.
"Unfortunately when you’re super fit, you’re really vulnerable to getting sick," she posted on Instagram.
"Covid caught up to me and I’m heartbroken to have to scratch the 5km and throw away another 12.5 laps of Hayward Field, but this one’s out of my hands.
"It stings a lot. For now I’m going to be a fan of Track & Field from my couch in Portland and recover ahead of the rest of the European season.
"Please, please, please know that I am truly proud of the race I put together on Monday night and this is by no means meant to suggest anything about the way I raced the 1500m final.
"Proud of myself and the people in my circle. Disappointed in the circumstances after my coaches and I have controlled every variable possible and I have been so methodically cautious to avoid a situation like this after 2+ years of training and competing internationally within the pandemic."
As a former University of Oregon Ducks track star, Hull is one of the most high-profile athletes at the world championships.
She is also the current Australian 1500m and 5000m record holder.
Assuming she recovers in time, Hull's next competition will be the Commonwealth Games in Birmingham, where she is among the medal favourites in the 1500m.
The opening round of the 1500m is set to take place on August 5.
There have been major concerns that the world championships could turn into a Covid-19 cluster.
The Japanese team has been badly affected, with 11 athletes and officials testing positive.
Mask-wearing is now mandatory for athletes, coaches, officials and media in indoor areas.
Eleanor Patterson wins gold in high jump
On Tuesday, Eleanor Patterson became the first Australian woman to win high jump gold at the world championships.
The 26-year-old needed three attempts to get over 1.98m just to stay alive in what was a high-standard competition and another two at 2.00m.
Then came a brilliant first-up clearance at 2.02m that equalled the Australian record and which turned out to be the gold medal-winning jump.
Patterson's great Ukrainian rival Yaroslava Mahuchikh needed two tries to get over that height, handing the Australian the gold medal on countback after 2.04m proved a bridge too far for both of them.
"I didn't make it easy for myself," said Patterson, who became just the 10th Australian to win gold at a world athletics championships.
"The calibre of women I was up against was phenomenal and they were clearing everything first time, they were doing amazing things.
"There were a number of moments where I had to dig deep to remain alive and also secure a medal and then see if I could stay on top of the podium.
"And somehow I've been able to bring that to fruition."
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