'I was on the terraces at Wembley that day,' he said. 'Chelsea had a great team Peter Osgood, Peter Bonetti and were probably better than us.
'But Gordon Banks made a couple of fantastic saves and we managed to hold out and win 2-1. How can I forget it? It's still the only major trophy we've won.'
Silverware: Stoke's 1972 FA Cup victory remains their only major trophy
Coates is a throwback in a league dominated in recent years by Russian oligarchs, debt-happy Americans and billionaire oil sheiks.
He spent his childhood watching Stanley Matthews and Neil Franklin at the old Victoria Ground and, when he bought the club from Icelandic owners in 2006, his motivation was glory rather than profit.
In the four years of his second spell in charge, Coates and his manager, Tony Pulis, have guided Stoke from the bottom of the Championship to their position as an established Premier League force.
Stoke run out at Chelsea on Sunday as that most unique of animals, a debt-free Premier League club, with their latest accounts showing the Coates family have given up their right to take back about £25million in loans.
International class: Gordon Banks is one of England's most distinguished players
Potty for the Potters: Stoke chairman Peter Coates
'Some foreign owners see a commercial benefit from football but I never did it to make money,' he said. 'I'm a local boy and my city is important to me.
'Getting Stoke in the Premier League has done more for the profile of The Potteries than any other event. Capitalising our family's loans was in the best interests of the club and the community.
'We were one of the great clubs. Stanley Matthews was the first truly internationally recognised player, pre-dating Pele, and we had another England player, Franklin. Billy Wright won 105 caps but always said, 'Neil was miles better than me'.'
Miner's son Coates, 71, who had sold Stoke in 1997, built a £200m fortune through catering and as owner of online bookmaker Bet365.
Sunday marks Stoke's first quarter-final for 38 years. They are under scrutiny following Ryan Shawcross's tackle on Aaron Ramsey but Coates added: 'We don't send out teams to cheat or intimidate.
'We play within the rules and spirit of the game. If that wasn't the case, I'd do something about it.'
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