Ian Thorpe was confused.
Aged 17, he knew the 2000 Sydney Olympic Games were a big deal.
And he knew his 400m freestyle final on the opening night of competition at Sydney's Games was massive.
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But waiting in the callroom before the race, Thorpe was baffled.
"I felt sort of confused. It didn't feel like the Olympics," he later said.
Then he entered pool deck with a sell-out crowd of 17,500 people chanting his name.
"As soon as I walked out, I realised how big this was," he said.
"It was just amazing walking out in front of the home crowd. The emotion really hit me."
Thorpe was the world record holder and world champion in an event his nation assumed he would win.
He could easily have been weighed down by the expectations; he could have fretted over a broken ankle just 11 months before the Games.
He could have worried about drug insinuations from Germany which some even related to his sized 17 feet.
But he didn't. His goggles were effectively blinkers.
"I have a lane and I swim," Thorpe said of his approach.
"If I focus all my energy and attention on what I'm trying to do, I'm going to be able to get my best performance.
"It's as simple as that."
But to the rest of the world, that 400m final was mind-boggling.
Within half a lap, Thorpe led by a body-length. At the first turn, he led by a second - an eternity in swimming.
The race turned into a procession. Thorpe broke his own world record by 0.74 seconds and won the first of five Olympic gold medals in his storied career.
His reaction? Jubilation? Exultation? No.
Thorpe looked at the scoreboard. Raised both fists and whispered 'thank you'.
He left the water with no real outward emotion. But inwardly, he was buzzing.
"I just felt this surge or sheer energy inside of me when I touched the wall and realised I had the world record," he said.
Australia marks 20-year anniversary of Sydney 2000
Thorpe and fellow Olympic hero Cathy Freeman were among those to recall the joys of the "greatest Games ever" at a special ceremony to mark the 20th anniversary of Sydney 2000.
Twenty years on and Thorpe revealed the depths of the pressure on his teenage shoulders to land Australia's first gold medal of the Games in the 400m freestyle.
"I didn't know what the Olympics was going to be like," he said during a rare public appearance.
"But I knew it would be a big moment and it was mostly because people would tell me that they'd won tickets in the ballot to go to the swimming on the first night.
"And they'd add something that kind of freaked me out: 'I can't wait to see you win your first Olympic gold medal', which is a lot of pressure and I went in and we hadn't won an Olympic gold medal at that stage.
"We thought we'd win one in the triathlon earlier in the day, so it was a big night."
Teenage basketball star Tenayah Logan and Paralympic track athlete Tamsin Colley had the honour of re-lighting the Olympic cauldron at Sydney Olympic Park on Tuesday morning.
Freeman, appearing via a video link from Victoria, said it was a wonderful gesture to have "two future stars" recognised on such a major stage ahead of hopefully the rescheduled 2021 Games in Tokyo.
With three gold medals and two silver, Thorpe, then only 17, was the most successful Australian performer in Sydney and, not surprisingly, he said it was the most memorable experience of his life.
"It sure was," he said.
"For me, I remember watching on TV at the start of the opening ceremony and it's amazing that 20 years have passed.
"For people to have the chance to reminisce about a time that was a great time for Sydney and the country where everyone was kind of celebrated (after) what had been a long build-up to the Games and then to be able to kind of get it going.
"It was a really healthy distraction watching on TV for me."