Azarenka's collapse caused by 'mild concussion' not searing heat

Belarussian No 10 seed hit head during warm-up but temperatures as high as 43C still take toll on players

Victoria Azarenka had been tipped by many as a possible winner of this year's US Open, but the 21-year-old from Belarus went out of the tournament in dramatic fashion here yesterday after collapsing on court. Heat exhaustion was initially blamed, but it later emerged that the world No 11 had suffered mild concussion when she hit her head in a fall in the gymnasium earlier in the day.

Azarenka had called for a trainer as early as the third game of her match against Argentina's Gisela Dulko. Thereafter she moved slowly and took her time between points, though there was little indication of what was to come when she was trailing 5-1 in the first set.

Having just hit a backhand, Azarenka suddenly fell to the ground. Medical personnel rushed to her side and Dulko helped to put an ice bag around her neck. She was eventually helped into a wheelchair and taken to a hospital nearby.

Dulko said Azarenka was conscious and responding to questions. "I was scared," she said. "She went to the floor. I was worried for her. I went to see her, brought some ice, did whatever I could do to help."

Assuming that heat had been to blame, Dulko added: "It's tough to play out there. It's really hot, really humid. You sweat so much, sometimes it's impossible to hold the racket."

However, Azarenka later revealed that she had hit her head in a fall while warming up for the match. "I was checked by the medical team before I went on court and they were courtside for monitoring," she said in a statement. "I felt worse as the match went on, having a headache and feeling dizzy. I also started having trouble seeing and felt weak before I fell. I was taken to the hospital for some medical tests and have been diagnosed with a mild concussion."

The heat could not have helped. The hottest summer ever recorded in New York City has been good news for suppliers of ice, 35 tons of which are used every day here, but the conditions have been tough for the players.

Azarenka collapsed just before midday, when the temperature was approaching 32C with 42 per cent humidity. It is not the first time she has left a court in distress during extreme heat. At last year's Australian Open she had to retire when leading Serena Williams, though her discomfort was also put down to a stomach virus.

For the last two days here the tournament has implemented its "extreme weather policy", under which medical time-outs for heat-related illness are allowed and a 10-minute break is permitted between the second and third sets of women's matches. The tournament referee can also postpone or suspend play because of the heat.

The on-court temperature during Andy Murray's victory yesterday over Lukas Lacko was 43C, which matched Tuesday's high, when the Serbian Novak Djokovic was among those who suffered. The world No 3 was on court for three hours and 40 minutes against compatriot Viktor Troicki before winning in five sets. His game picked up significantly when the court went into shade.

Ivan Ljubicic was one of several players who wilted in the heat yesterday. "The weather was my biggest enemy," the No 15 seed said after losing to Ryan Harrison, an 18-year-old American qualifier. "Throughout my career I struggled with the heat. Today was no different."

He added: "We saw some players struggling big time. There are comments saying it's the same for everybody, but really it's not. Some people struggle more than others and I think it's just not fun. I think people out there are coming to see good tennis, and on days like this it's all about everything except tennis."