Having finished his celebrations at 5am, he had woken to give an 8.30am interview to the BBC, who had transmitted his finest hour to an audience of millions the previous night. Now came the press conference. And to follow, a guest appearance at one of the many kit sponsors suddenly vying for his signature. Meanwhile, back at the home in Canvey Island he shares with his parents and brother and sister news reporters were gathering.
After two years of injury - repeated stress fractures to his foot required the insertion of a metal plate and seven pins - during which he wondered "thousands of times" whether it was worth continuing with athletics, this 21-year-old giant had arrived, big time. And he was completely ready for it.
"I love the attention," he said. "I honestly can't wait for everything that is going to happen. It's what I have been dreaming about for the last two years. Every time I saw guys like this [he gestured to the man sitting beside him] on the television, it would be, `I want to be there, I want to be there'."
In the space of a few hours, he discovered that was where he was. He woke up to an invitation for next May's elite decathlon in the Austrian town of Gotzis.
Later in the day, the commercial value of a young man whose petrol-money worries were over for the foreseeable future - $30,000 (pounds 18,900) for his medal will clear any outstanding bills - was evaluated by Dean Jackson, the UK marketing director of Asics, who have been first of the sportswear manufacturers to begin negotiating with him.
"If things go well, he can be the biggest British athlete of all time in marketing terms," Jackson said. "He can win his first million by winning the Olympics next year." Money clearly is not uppermost in Macey's mind. "I found out last night there was prize money" he said, grinning broadly beneath his shock of bleach-blond hair. "I didn't know. I would have won if I'd known." Questioned over his time as a central defender on Arsenal's books, it was suggested to him that he might have ended up as another Tony Adams. "I'd rather be sitting in this position," he said.
When it comes to analysing how he can improve after his first senior international event, however, Macey's attention focuses critically on the two days of action in which he set personal bests in six events.
Given that the 10-discipline demands of the decathlon, similarly to the marathon, make it unfeasible to contest more than two or three a year, Macey is already looking closely at the 2000 Games in Sydney.
"I believe I can win it," he said. "I honestly do. I said I wasn't coming here just to make up the numbers, and now I have proved that I can compete." For anyone doubting the strength of Macey's will, the story of how he competed at the European Under-23 Championships in July just two weeks' after he and a friend had been savagely beaten by a street gang in Canvey Island serves as a salutary warning.
"It's not the sort of thing I want to remember," he said. "There was a good few of them, just fellas coming out of a nightclub. I had concussion and my shoulder was dislocated. It still gets a little bit sore. But it takes more than a couple of bottles and stuff to stop me." It is onwards and upwards for the man whose only previous job was as a lifeguard at the local leisure centre.
In October he will travel to train in Australia with Estonia's European champion, Erki Nool, in company with his coach, Greg Richards, and the man whose achievements in the event still stand as a looming challenge for any Briton, Daley Thompson.
While Richards, who competed at decathlon during the Thompson era, is Macey's coach, the self-styled "godfather" of the event is taking a paternal interest in the ebullient newcomer whose mischievous sense of humour resembles his own.
But the former world and Olympic champion is sensibly cautious in his analysis of Macey's prospects. "The good thing with Dean is that there is lots of room for improvement," Thompson says. "But let's get this in perspective. The world record holder had a very bad day and he beat Dean by miles. Dean may be challenging for the top spot in three or four years' time, but it's unfair to him to say that he will do it any earlier than that. There is still a lot of work to be done with him." For Jackson, there remains only one thing to be done - to win the Olympics.
Acknowledging the extra time he requires to recover from races at the age of 32, he will scale down his racing programme next season in order to prepare for that ambition.
But for now, he can revel in re-establishing himself as the event's No 1. "It was one of the greatest feelings I've ever had to return from the dead," he said. "To be world champion again was unbelievable."Reuse content