For the first time on his watch Everton took on Manchester United at their own game - and won.
Sure, the benchmark by which all successful sides must be judged have been beaten by a David Moyes team before.
But only on a night when Everton suppressed United's flair, pressed, closed and defended for their lives, then hit the visitors with a set-piece counter-attack.
Not on Saturday. Not in front of an increasingly impressed Goodison crowd.
Everton watched Manchester United start well, exert some superiority and land an early blow - then they borrowed a phrase from Muhammad Ali.
They muttered: 'That the best you got sucker?' and shook up the Premier League world.
Most post-match analysis focused on United's deficiencies.
But happily more and more are waking up to the excellent football team which is hatching at Goodison Park.
The Blues swept the champions aside with a classy display of passing football. The yellow cards they picked up were either for trivial misdemeanours or Howard Webb's willingness to appease the red-faced ogre in the away team dug-out.
And what was even more compelling - more so than the way in which the absence of stellar players like Marouane Fellaini, Tim Cahill and Phil Jagielka was overcome - was the fact that this was not an isolated triumph.
Fearsome, formidable February is suddenly becoming fabulous.
To win well once against a 'big-four' side might be an accident. Twice, a coincidence. But three elegantly crafted victories in less than a month against opposition as expensively assembled and ambitious as Chelsea, Manchester United and Manchester City - and almost Arsenal, too - suggests something may, finally, be stirring again at Goodison Park.
We've been here once or twice before since 1987 of course.
But certainly not as often as we'd like. The make-up of modern football means that without sudden injections of cash, any assault on the higher reaches of the Premier League has to be a patient process.
But quietly, stealthily, unheralded almost, Everton have claimed back-to-back fifth-placed finishes and an FA Cup final appearance.
All that's been missing have been victories over the most difficult to beat teams. Now Blues fans have celebrated two in a week.