Nigel Sears has given a detailed description of his public collapse at the Australian Open, telling theTimes he still does not know what caused it but suspects it was an allergic reaction to sushi.

In an extensive interview at the WTA Dubai event, the coach of Ana Ivanovic and father-in-law of Andy Murray said he began experiencing problems while watching the first set of Ivanovic's third-round match against Madison Keys at the Australian Open.

"I was feeling really dizzy, even though I was sitting down, and began to sweat a lot," Sears said. "I was convinced I was about to throw up and decided I had better head for the restroom."

Sears said the next thing he remembers is regaining consciousness surrounded by medical personnel who were applying pressure to his chest. But he said it was not a heart attack, though doctors have still not identified exactly what happened.

"I had sushi for lunch ten days in a row in Melbourne and was fine," he said. "But I suppose... you get one dodgy bit of raw fish in that time."

The incident led to dramatic scenes as Sears was taken off in a stretcher while play was stopped in the stadium. Murray played on elsewhere, unaware of what was happening. Murray's wife, Kim Sears, was pregnant and back in Britain.

Sears was apologetic for creating all the fuss but added that at least it had not happened when he was "in my hotel room when I was all on my own."

"I know I was such big news at home," he said. "But it was a really strange one and I'm just really sorry I worried a lot of people unnecessarily."

Murray and Kim Sears have since become parents to a girl. According to Nigel Sears, the new parents named her Sophia.

The coach encouraged Murray to keep playing the Australian Open, with the No. 2 reaching the final. Murray was told what had happened following his own match against Joao Sousa.

"He was great, he came straight to the hospital in the tennis clothes he’d been wearing during his match and stayed with me for a long time," Sears said. "Andy was naturally concerned, but the important thing was he could start relaying stuff back to Kim and her mum because they obviously wanted to know what was going on."

Sears is in Dubai coaching Ivanovic, who has reached the quarterfinals.