Start of Phelps' farewell Olympics
Phelps mania about to hit Rio as record-breaker gets set for first big splash
Smartly clad in black and dark blue suits, and grey, Japanese officialdom, all in typically sombre colours, are out in force here.
They see and scrutinise, they query and listen intently, they absorb, take notes, huddle and discuss, all to learn lessons - what to do and what not to do, what must be done and what they can improve on four years from now when they host the Olympic Games.
Everyone knows Tokyo 2020 will be special because the Japanese studiously learn, and get it right.
Four years from now, sports-mad Japan will be Olympic-mad, the facilities in Tokyo will be ultra-modern, volunteers will be bright, chirpy and smiling, helpful and, crucially, knowledgeable.
The transport system will hum precision and showers will work warm water and cold well.
But Sydney, Athens, Beijing, London, and now Rio, will always be able to show off something Tokyo will never have - Michael Phelps.
Barring disaster, the most Olympic of Olympians will swim in his first final of his last Games in Rio today - it is an all-ticket event, and I have one.
Phelps will surely skip the men's 4x100m freestyle heats here in the afternoon (early this morning, Singapore time) - when you have Greatest next to your name, you enjoy such privileges - and if the initial American quartet ensure progress, then he will take his place in the starting four in the final.
With all eyes on him, he goes for gold No. 19 in his first competitve swim of probably five or six events at the Olympic Aquatics Stadium.
It was already a raucous arena on the first day of swimming, with three world records and Australia announcing their return as powerhouses in the sport.
It's about to get louder.
This will be Usain's final Olympics but the lightning Bolt is still going to crackle at next year's World Championships in London.
The Jamaican track superstar will continue to burn up sprinting, but these Games will stage Phelps' final splash in competition.
The excitement will be electric because of him, and because the United States are eminently beatable in an event they used to rule.
He was a student at Sydney 2000, but started his special relationship with Olympic cities four years later.
At Athens 2004, Phelps, then 19, was part of an American quartet who could finish only third in the 4x100m freestyle relay, as the South Africans stormed to gold in a world-record time ahead of silver-medallists Holland.
With Phelps at his peak in Beijing in 2008, the US stormed to gold with a new world and Olympic record of 3min 08.24sec.
With Phelps deciding to skip the event, the French musketeers beat the US to gold in London four years ago.
With the retired Phelps missing at the last two world championships, La Marseillaise again soared the loudest in the event on both occasions, while the Americans collected silver in 2013 in Barcelona and failed to make the final in 2015 in Kazan in a huge shock.
But Phelps is back, now 31, experienced, at ease with himself after carrying the weight of expectation for 12 years.
He's a father of infant son Boomer and enjoying the Olympic experience like never before, he says.
Barring a calamitous disqualification, he will know his team will be in the final of the 4x100m relay at approximately 10.52am this morning, almost certainly alongside a dangerous Russian quartet, and the Australians, Italians and possibly the hosts.
And the reigning champions France, of course.
Curious, I was at the stadium early yesterday morning and the pool was still as glass.
There was much quiet, with hardly anyone around. The army guard approached, pointed at the water and, inexplicably, muttered: "No Michael Phelps."
He laughed, poking fun at someone he thought had got his schedule wrong.
I didn't, although I cannot say the same for the transportation times here.
The Japanese won't fluff such lines in 2020.
They will have space-age gizmos in Tokyo to help with up-to-the-minute information and maybe even driverless trams within the Olympic Park.
Fresh delectable sushi and sake may be served via vending machines.
There will be big stars at Tokyo 2020, but only four Olympic cities will forever be linked with Phelps.
He won six golds in Athens, a mind-boggling eight in Beijing and four in London.
Rio will enter hallowed company, when he begins his treasure hunt this morning.