For both managers this semi-final felt like a moment of truth. Roberto Di Matteo could see it as a confirmation that, out of what looked like a mutinous rabble under André Villas-Boas, he has created a momentum that could take Chelsea to heights undreamed of six weeks ago. As for Harry Redknapp, if the Tottenham manager does accept England's poisoned chalice, he will not want to experience any more Wembley occasions like this one.

Di Matteo, who has his own golden memories of FA Cup glory at Wembley, now appears to be that most enviable of football creatures: the manager blessed with luck. On Sunday he saw his side take a two-goal lead against the run of play, crush an incipient Spurs revival with a goal that needed an outrageous slice of help from the officials, avoid the expulsion of his goalkeeper and ultimately romp away with what amounted to a landslide victory as they scored goals almost at will against their demoralised opponents.

As the man in charge of the side allotted the home dressing room, Redknapp sat in the chair once occupied at the new stadium by Steve McClaren and Fabio Capello, and after this ultimately calamitous result – to go with only one win in Tottenham's last eight Premier League fixtures – there will be even more speculation about whether he is the right man for the job.

It is impossible, however, to ignore a moment of pre-match ignominy that will leave a lasting stain on the Wembley sky. Incapable of behaving like civilised human beings even for the briefest moment, a section of Chelsea's fans disrupted the silence requested in joint commemoration of the Hillsborough victims and of the sudden death of the Italian footballer Piermario Morosini. Had Martin Atkinson given it a full minute rather than blowing his whistle to end the gesture of respect after not even 30 seconds had elapsed, goodness knows what would have happened. Chelsea issued an official expression of regret but they must be made to devise substantive action against such outrages.

As if Saturday's dreadful first semi‑final between an undistinguished Liverpool and an unadventurous Everton had not been enough to dull the appetite for football, that episode made it even harder to welcome the second match with a glad heart. At least there was plenty of drama in store, including a moment of rank injustice which placed yet another giant question mark against the lapses of judgment being displayed by English football's top referees.

Two surprising selectorial decisions, one on each side, prefaced the encounter, and how differently they turned out. Di Matteo had picked Didier Drogba instead of Fernando Torres and was rewarded with a goal, two minutes before half-time, to match any the veteran Ivorian has scored in the blue shirt. "I don't know whether Wembley loves me," Drogba said a couple of years ago, "but I love Wembley." As he wheeled away from William Gallas and lashed a left-foot shot high inside the angle of post and crossbar, he was celebrating the blow that revived memories of past glories and drained the optimism engendered by Spurs' early liveliness.

The man beaten by that thunderbolt from the blue was Carlo Cudicini, the surprise selection by Di Matteo's opposite number. The Italian goalkeeper had played in all five of his side's previous matches in the competition this season, and it was in keeping with the much abused spirit of the Cup that Redknapp retained him in the starting lineup for this match. Ten years ago Cudicini was voted player of the year by Chelsea's supporters and here he was appearing at the opposite end from Petr Cech, the man who displaced him in the Stamford Bridge goal two years later.

The 38-year-old Italian has been in some senses an unlucky player throughout his career – unluckiest of all, perhaps, to have grown to a mere 6ft 1in, two inches shorter even than his father, Fabio, who won the European Cup in 1969 with Milan. The son made several brave and skilful saves in this match but they were all overshadowed by his failure to keep out the 35-yard free‑kick with which Frank Lampard stretched the lead to 4-1 and applied the final choke to Spurs' attempted revival in the 81st minute.

The ball was struck with a dipping accuracy reminiscent of Cristiano Ronaldo at his best but from a range of 35 yards it should have been intercepted as it made its way just inside the right-hand post. Fatally Cudicini had made his first move in the opposite direction but the failure also exposed once again his lack of height and reach.

Cech, by contrast, had enjoyed a moment of supreme good fortune when he brought down Emmanuel Adebayor 10 minutes after half-time. Gareth Bale's success in tapping home the loose ball to make the score 2-1 rendered the award of a penalty unnecessary but it should not have stopped Mr Atkinson dismissing the goalkeeper.

A match that had been prefaced by ugliness ended in the squalor of a scuffle between Scott Parker and Mikel John Obi. At the final whistle Redknapp shook his opponent's hand and rushed away down the tunnel, blank-faced but with more on his mind than a lost Cup tie. For Di Matteo, having somehow got Chelsea to play winning football, the obstacle represented by Barcelona will now seem a little less insurmountable.