Now, this is not to denigrate that performance, away from home against a wonderful team, but there is no comparison. On Wednesday's display the contemporary United would have slaughtered the team of Best, Law and Charlton.
Heresy? Watch the games on video. Much of the earlier match was played at near walking pace and, though there was a lot of largely unpunished brutal fouling, space in most parts of the pitch was widely available and Benfica's defensive marking was diabolical.
Wednesday's match was played at high speed throughout with players closed down the moment they had possession. United's work-rate was as phenomenal as their skill and movement. As Gary Pallister, who illustrated United's confidence with one second-half break-out, said: "It was a bit like watching Juventus against us in Turin. Everyone chased the ball and hunted down any Porto player who had it.''
Obviously, given modern training methods and playing disciplines, most of the old masters would be as impressive as their successors. Application is easier to instil than skill, though not everyone can manage it. Even so, the contrast demonstrates just how much the game has moved on and just how good modern football, for all its critics, is.
Wednesday night also suggested that, with astute management and intelligent play, English clubs can again match the best in Europe. It is a dozen seasons since an English club, Liverpool, reached the last four of the Champions' Cup. That season ended in tragedy and exile at Heysel. Since English teams returned to the competition in 1992, Arsenal, Leeds, Manchester United twice, and Blackburn had all failed to even reach the last four.
Now United, barring a catastrophe in Oporto in 12 days' time, will be there. They would meet either Borussia Dortmund or Auxerre; the German side lead 3-1 from the first leg but will have the dismissed Stefan Reuter suspended for the second. Yesterday Uefa was not sure if his suspension would also affect the semi-final. Who plays at home first will be decided by a draw in a fortnight.
United would then be two games away from what would be a very emotional final - the game is to be played in Munich, the city in which the Busby Babes died.
Manchester United's victory was a triumph for Alex Ferguson's tactical awareness and his players' ability to learn from their earlier European misadventures. While it was the style of their victory which caught the eye, their defensive concentration was equally impressive and just as crucial. After an early stutter they locked Porto out completely. The match may come to be seen as a turning point for Ferguson's United, a coming of age.
Alex Ferguson will have been particularly pleased at the way his team kept going. He continually complains that they struggle to kill off teams and, at half-time, one wondered if they could retain the tempo, concentration and passion.
The only blot was a silly and out-of-character booking for Denis Irwin, for kicking the ball away. United still have the best disciplinary record of the eight remaining sides. Though suffering seven bookings - Irwin, David Beckham, Eric Cantona, Roy Keane, Gary Neville, Ole Gunnar Solskjaer and Jordi Cruyff - they have yet to suffer a suspension. Porto, who will have three players suspended for the second leg, have had 16 yellow cards and Atletico Madrid 20.
It is this type of discipline which is likely to gain England an extra Uefa Cup place as one of the top three countries in the European fair- play league. They are currently first.
Incidentally, if United win the cup and also finish in the first two of the domestic league, as seems likely, England will not be given a third place in the expanded Champions' League
United's win will have given Glenn Hoddle mixed feelings. While the national coach will have been delighted at the performances of the five English players, the victory increased the likelihood that they will not be available to him this summer.
Ferguson's threat to withdraw his players from the French tournament to rest them may seem unnecessary to some. After all, even if United win the European Cup they will play only 54 matches this season including the Charity Shield. No Premiership side, not even Wimbledon, will play 60, while Everton will play just 42. When Tottenham won the Uefa Cup in 1973, they played 70.
However, we come back to the speed of the modern game. "It has got faster and more physical," said Pallister, no stranger to overuse injury, "yet we still play 50 games a season. I don't know how long players have got to keep voicing their opinion that we play too much. There is enough money in the Premiership now to allow the league to be streamlined.''
Dream on. Taking away two home games would cost United nearly pounds 2m in gate receipts and spin-off income. For them that can be counterbalanced by the pounds 10m added to their share value within half an hour of the Stock Exchange opening yesterday morning in the aftermath of Wednesday's win, but not many clubs have that luxury. They are no more likely to give up those games than United are to surrender their lead.
VERDICTS ON UNITED
In such an important game and against a team with such a great record, it has to be one of the best performances since I came here. Alex Ferguson.
It was a lot better than we dreamed of. Doing Doubles, winning championships and cups and having good runs in Europe is what every chairman is looking for. Martin Edwards, United chief executive.
It was like the 1960s all over again. The players were magnificent in the way they approached the match and the fans went wilder and wilder with every goal. The whole of Europe will be frightened to death. It will take a miracle for them not to go through now. Paddy Crerand, midfield schemer in the great side of the 60s.
At this club the European Cup is the one thing that will always be shoved down our throats. Even when we win the domestic league, we're told we're not true worthy champions because we've not done it in Europe. The desire to put that right burns within all of us. Then we want to win the world championship - that's the desire you have to have to succeed at the highst level. Gary Pallister.
Wednesday was a good performance, but it's only half the loaf for us so we're not getting carried away. Andy Cole.
We will try to do our best to give United a proper game in the home leg. We hope to improve our football so that we'll be a better team in the future. Antonio Oliveira, Porto coach.Reuse content