Darren Campbell knows all about the euphoria of winning an Olympic gold medal.
At the 2004 Athens Games he and his four team-mates were overwhelming underdogs in the men's 4X100metres relay race. It was a race regarded as the USA's right to win; more of a given rather than a contest.
Four years previously at Sydney, Maurice Greene, Jon Drummond, Brian Lewis and Bernard Williams not only won comprehensively, but then posed for a multitude of body-building poses as other competitions occurred in the background.
Justin Gatlin, Coby Miller, Shawn Crawford were newbies for the Americans, yet the formidable Greene still loomed. But as he accepted the baton in the final dash, Mark Lewis-Francis held off the American for one of the most memorable British sporting moments of the 21st century.
"We used the negativity from the media to drive us on," Campbell recalls of that balmy Grecian evening. "They kept on bringing up the qualifying rounds and how we were in a false position and couldn't get any lower.
"But it played out as I hoped it would. That feeling when it was over is indescribable."
Campbell sheds tears of joy on the podium
A silver medalist at Sydney 2000, Campbell was at the forefront of the Team GB resurgence, after Steve Redgrave and Matthew Pinsent won the UK's sole gold medal at Atlanta 1996.
He concedes that despite the low expectations eight years ago, it was initially impossible to relax.
"The enormity of it dawns on you when it's moments away. I was in awe and struggling to concentrate, taking in the surroundings at first, so you can only imagine how they'll feel this time."
This time there is optimism. Not solely because the 2012 Games are on British soil, but because Great Britain finished an extraordinary fourth in the medal table at Beijing in 2008.
"For me, the nerves subsided as the race drew closer," he reveals.
"Hopefully though the crowd will make it easier for them. There's a lot of enthusiasm and it's not even started yet. It's great to see the turnout when you're holding the [Olympic] Torch, let alone what it'll be like inside the stadium.
Campbell, 38, is an ambassador for the Special Olympics, in between his sprint coaching duties, and is determined to lend the event more exposure.
"When you see the joy they get out of just participating, that is when you understand how special it is not just for them, but for me as well as a representative," he extols.
He was due to run the 10k Nike Run on 8 July, but had Sale Sharks and England rugby winger Mark Cueto's wedding to attend.
"I would like to say the wife's dragging me along," he laughs honestly.
Darren Campbell has been an Ambassador for Special Olympics GB since 2007. For more information, visit www.specialolympicsgb.org.uk