In a managerial reign at Manchester United that has spanned almost 25 years and has included so many trophies, the beauty of Sir Alex Ferguson's fourth Champions League final later this month is that it has the potential to be as significant as any other.
Ferguson's standing in history was assured a long time ago and his legacy will still be remarkable whatever happens against Barcelona at Wembley on 28 May. But for a man who is addicted to winning, and winning against the biggest and the best, there is no one to match the modern-day Barça as the most daunting opposition of all time. Beating them in the biggest game of all would be just about as good as it gets.
Ferguson described Barcelona last night as the "team of the moment" but most would say that they are a bit more than that. This Barça team are, at the very least, the side of their generation, as close to a dominant force as we have known in a competition that, in its current format, has never been retained by any club. They are the kings of European football and only Ferguson and his players stand between them and their coronation.
It is remarkable that 37 years since his managerial career began at East Stirlingshire, and now in charge of the most powerful force in English football, Ferguson will still be able to play his oldest trick – that of claiming the underdog status – at Wembley this month. But underdogs are what United will be in their third Champions League final in four years, against a team the bookmakers have already made odds-on favourites.
So much history will come together at Wembley, 43 years after Sir Matt Busby's team won the club's first European Cup there. As far as the likes of Ferguson, Paul Scholes and Ryan Giggs are concerned these are the final chapters of the story and this game, especially the consequences of a United victory, have the potential to be the most significant events in the club's history for decades.
What will Ferguson do if he wins United's fourth European Cup this month? His disclosure last night that he speaks regularly to Jose Mourinho did nothing to alter the sense that Mourinho's accession to the Old Trafford job is a done deal when Ferguson finally steps down. There would be no better way for him to leave than finally unpicking the mystery of Barcelona and walking away having beaten what some people are already saying is the greatest team ever.
Before then he has to wrap up the record 19th league title in United's history with the game against Chelsea on Sunday likely to go a long way to deciding it. It is hard to draw many conclusions about United's current form from last night when they swatted aside a Schalke team who were well out of their depth.
The next 23 days will pose much greater tests for Ferguson, who made nine changes from the team that faced Arsenal on Sunday. Wayne Rooney, Rio Ferdinand, Park Ji-sung and Michael Carrick were left out the squad. Jonny Evans, Chris Smalling, Darron Gibson and Dimitar Berbatov all started the game and Ferguson kept a few of the big guns on the bench just in case .
In the end he did not need to call on the likes of Giggs, Javier Hernandez and Nemanja Vidic because Schalke were as bad as they were in the first leg. Their Spanish midfielder Jose Jurado scored in the first half when United were two up but the mini-riot the away fans started in the East Stand was about as fierce as it got from the Germans.
From the moment Antonio Valencia opened the scoring on 26 minutes this game was only going one way. Manuel Neuer, in the Schalke goal, needed to perform as well as he had against United in the first leg but he never got close. Darron Gibson, not every United fan's cup of tea, played well and scored another in the first half. After the break, the Brazilian midfielder Anderson scored the third and fourth goals of his United career.
For Gibson, making just his 14th start of the season, this was a significant chance to impress. His second major pass of the evening made United's first goal. Schalke's carelessness gifted possession and United worked the ball right to Gibson who played a pass in behind Schalke's left-back Atsuto Uchida. Valencia ran onto it and hit a shot through Neuer's legs.
The Germany goalkeeper, outstanding last week, was not exactly at his sparkling best last night. He was badly at fault for United's second goal, a low drive from Gibson that Neuer failed to get behind properly and which cannoned off him and in via the post.
The tie was over and it was only poor defending from United that let Schalke in again. Smalling gave the ball away the first time before United had another chance to clear when the cross came into the area. They only got it as far as Jurado who picked his spot well.
After the break, the famously non-scoring Anderson took advantage of Schalke's weaknesses. His first came when the excellent Nani broke down the right and crossed. Anderson made a mess of his first effort but then turned sharply and shot to beat Neuer. Four minutes later Nani played in Berbatov and his ball across goal found Anderson at the far post.
In injury-time, Michael Owen, a notable absentee from a 4-3-3 formation that could only accommodate one centre-forward, forced the best save of the match from Neuer. There were no major United celebrations at the end of the game – not least because there is still so much to do.
The debate had already started last night as to how United will beat Barcelona's passing machine. No doubt someone will say over the next few weeks that beating Barça will be Ferguson's greatest-ever achievement. That might be simplifying matters a little too much but one thing is for sure: it would be an incredible way to say farewell.
Man of the match: Nani.
Match rating: 6/10.
Referee: P Proenca (Portugal).
Champions League final
Barcelona v Manchester United, Saturday 28 May, 7.45pm, Wembley. ITV 1, Sky Sports 1