Man Utd pile on agony for Wenger
Sir Alex Ferguson and Arsene Wenger were inches apart but heading in opposite directions - one pondering fresh possibilities to make history and the other starting a critical period of soul-searching.
Manchester United had brushed Arsenal aside with a savagery, speed and ruthlessness that had plenty of observers at the Emirates labelling it as this sport's equivalent of Manny Pacquiao's demolition of Ricky Hatton.
So while Ferguson was presented with the possibility of making Manchester United the first club to successfully defend the Champions League, Wenger was dealing with the pain of four years without a trophy and the problem of how to bridge the gaping chasm between these two clubs.
The scale of this defeat was etched on the lines of Wenger's face as he attempted to come to terms with the blow he and Arsenal had just suffered in the aftermath of what might be a pivotal night for his club.
Wenger boldly promised those gathering at the Emirates that they would see "a magnificent performance". They saw one all right - but they saw it from Manchester United.
Ferguson, in a masterpiece of understatement, reacted to what was effectively a 3-1 thrashing by annoucing that his team "has got a lot going for it".
He was not kidding. It has Wayne Rooney and Cristiano Ronaldo going for it, plus the real chance of winning the Premier League and Champions League for the second successive season.
And Ferguson was as unforgiving as his team as he sat in the Emirates media theatre reciting the list of qualities exemplified by this Manchester United performance: "Ambition... hunger... drive... ability to play under pressure... when the chips are down they don't let me down."
And so it went on. It would not have made happy listening for Wenger as he waited in the wings for Ferguson to finish. Verbal blows were being layered on top of the footballing beating that had just been handed out to Arsenal.
Of course Wenger rightly highlighted young Kieran Gibbs' early slip that gifted United's first goal to Ji-Sung Park, the moment when a cacophony of sound swirling around the Emirates was silenced after only eight minutes and a few thousand feet were added to Arsenal's already mountainous task.
Manuel Almunia's case to become England's number one keeper - and this particular bandwagon should stop rolling now on a matter of principle as well as ability - suffered a blow with his a slow-motion reaction to a 41-yard free-kick from Cristiano Ronaldo.
Only 11 minutes gone. United two up. Arsenal were shell-shocked and the thousands of flags distributed around the Emirates to crank up the atmosphere were being quietly tucked away under seats.
The rest was merely a question of bearing witness to United's procession to the final in Rome against either Chelsea or Barcelona - but it was a procession decorated by a goal that ranks alongside any in this or any other season.
Even in places where praise for Manchester United and Ferguson is always grudging, United's third goal must be beyond dispute as a thing of footballing beauty. It was a portrait of the game at its finest.
United struck from an Arsenal corner after 61 minutes when Ronaldo - 20 yards from his own goal - found Ji-Sung Park with an audacious flick, who in turn played in Rooney.
Rooney then passed on an open invitation for someone to score, and that someone turned out to be Ronaldo, who had raced 70 yards at blinding speed and still retained enough composure to lift his finish over Almunia.
It takes almost as long to describe it as it did to score it. It was that fast, that clinical, that good.
This was more than some Arsenal fans could take as the exits suddenly got busy, but it was an illustration of Ronaldo's importance to United on a day when he was once again touted as a summer depature.
United would be as foolish to sell him as he would be to sign for Real Madrid. And fine player though his alleged replacement Franck Ribery might be, I do not recall him producing a performance as all-encompassing and defining as this.
We have all raged at Ronaldo's posturing at stages this season, Manchester United fans included, but here he was at the top of his game. Arsenal sought him here, there and everywhere as he played as a lone striker with Rooney handed a left-flank role.
They sought him in vain as he operated with pace, poise and a deadly finishing touch that made a mockery of the old allegations that he was never able to shape the biggest games in the Champions League.
Darren Fletcher's undeserved red card was United's only moment of discomfort - but for Wenger the painful process of assessment and rebuilding must now begin.
Wenger was uncharacteristically upbeat after Arsenal were outplayed at Old Trafford last week and was equally bullish in the verbal exchanges before this game.
None of what he said about how Arsenal would turn this tie around was backed up by anything seen in the first leg. Why the positive message? Did he know something?
Maybe he did. Maybe he knew he had to be positive for his Arsenal team because they were having trouble being positive for themselves - it could be an argument with merit because they never carried a sense of belief with them in either of these games.
Arsenal's season is effectively over and they are exactly what they are. They are the fourth best team in the Premier League and a club that, in its current guise, will make the later stages of the Champions League but never win it.
The Carling Cup and the FA Cup will always be realistic targets for Arsenal, at least this version of Arsenal, but the Premier League and the Champions League? No. Sorry.
Arsenal are currently behind United (obviously) but also Liverpool and Chelsea and Wenger will need to work the markets with the expertise of old to stop the gap widening to an unmanageable level.
Wenger admitted this night ranked alongside the most disappointing of his career - but the wounds were too fresh to consider the long-term future for Arsenal's team.
He did hint at change, however, when he said: "We were on a consistent run, but recently in games the games where it mattered like the FA Cup semi-final against Chelsea and tonight we couldn't win and that, of course, needs thinking."
The body language was that of a manager who had been cruelly and closely acquainted with the vast superiority of the team he must overhaul if he is to cure his obsession with bringing the Champions League to Arsenal.
It would have been a hard heart that did not feel sympathy for Wenger, a manager full of the finest football principles who has produced great teams and loves to pack them full of young players with potential.
But when does unfulfilled potential simply become a substitute phrase for failure? Four seasons without a trophy comes pretty close and Arsenal will continue to come up short unless Wenger takes decisive action this summer.
A midfielder of presence and authority is needed to go alongside Cesc Fabregas in midfield, while a central defender in a similar mould must also be a priority. And that is just the start - while also ensuring his best players stay in north London.
This was a chastening night for Wenger and Arsenal. The Gunners are empty-handed again. Almost but not quite - again. The hurt may well linger through the summer until the start of next season.
No such worries for United. They have become turbo-charged almost from the moment Howard Webb awarded them that dubious penalty against Spurs.
It acted as a reviving force for them and history is now ready to embrace Manchester United and Ferguson in again in Rome.