Was this shock bigger than Wimbledon in 1988? Was it the biggest since Sunderland in 1973? These were the questions being asked here last night, but it was another FA Cup final that came to mind while watching Callum McManaman tear Manchester City apart.
In 1978 Ipswich Town upset Arsenal 1-0 with a goal from a hitherto unheralded midfielder, Roger Osborne. Yesterday Ben Watson filled that role, but it was another Englishman whose performance prompted the comparison.
The key player 35 years ago was a young winger who was just emerging on the scene, David Geddis. The player who set the tone yesterday was another fresh native talent, Callum McManaman,
Back in 1978 Geddis was so impressive that even the football agnostic Margaret Thatcher, then Leader of the Opposition, recognised it. Unfortunately she did not recognise him.
In those days players did not wear their names on the backs of their shirts and no one had informed Thatcher that there had been a change in the teams in the programme. So when asked for her man of the match she said: "Ipswich's No 10, Trevor Whymark, played well."
McManaman's name stretched across his No 15 shirt but were it not for a tackle in March he would be equally unknown. The late-developing 22-year-old from Huyton, the Liverpool suburb which also produced Steven Gerrard, Peter Reid and Joey Barton, was castigated for a terrible challenge on Newcastle's Massadio Haidara.
It was McManaman's debut and the criticism rumbled on because the referee Mark Halsey failed even to award a free-kick so that the issue was not put to bed on the day. Lesser characters would have gone into their shell but McManaman has continued to show the form of his previous match, the FA Cup quarter-final at Goodison Park, in which he scored. The goal was especially sweet as he had been on Everton's books from the age of seven to 16 before being released by the club.
"I can't believe [what's happened] to be honest," said McManaman last night. "I'm made up. I just had a feeling this morning when I got up that I just knew it was going to be our day.
"The longer it went on, we knew we had the better chance. Eventually the goal came. The gaffer said before the game, 'Just treat it like any other game. Go into it, don't be afraid'."
Geddis's career never lived up to the promise that he showed at Wembley but McManaman has every chance of progressing further. His sensational end to the season could even catapult him into the national squad for the forthcoming South American tour, for while the England manager Roy Hodgson had few of his compatriots to watch yesterday, the winger's performance made his attendance worthwhile.
Martinez is confident that whatever comes his way McManaman will remain unaffected. "He doesn't care about wearing the best shoes or driving the best car, but give him a football and he is happy," said the Wigan manager, adding: "He is one of the big diamonds in English football."