A goal behind from the first leg, Sir Alex Ferguson's men blew their opponents away with four first-half strikes from Michael Carrick, Alan Smith, Wayne Rooney and Cristiano Ronaldo. Further efforts after the break from Ronaldo, Carrick and Patrice Evra completed a remarkable 8-3 aggregate success for a United team who will fear neither prospective semi-final opponent, AC Milan or FC Bayern München, after this display.
England international Michael Carrick, receiving the ball from Cristiano Ronaldo 25 yards out, curled a delightful chip over the stranded Alexander Doni in the visiting goal to send the home fans into raptures and sends their hopes soaring. Minutes later a second goal followed from Alan Smith - only in the side as a replacement for injured Louis Saha and a surprise selection ahead of Ole Gunnar Solskjaer at that – and then immediately the third goal went in, first-leg hero Wayne Rooney bagging it from close range.
Ronaldo added two of his own either side of half time while another from Carrick and a seventh strike from substitute Patrice Evra completed the rout, Daniele de Rossi grabbing a stylish consolation!!!
The game began at 100 miles per hour, United with the majority of the ball as an electric Old Trafford roared them on. However the first three shots were directed at the goal of Edwin van der Sar. First David Pizarro sent one a few yards wide, which did not especially trouble the Netherlands international, before Francesco Totti unleashed a snaking grass-cutter fractionally past the post that certainly had him worried. The Red Devils' defence learnt their lesson and made sure to close down the playmaker, doubtful until just before kick off, at every opportunity.
Mirko Vucinic had a wayward attempt in the eighth minute, followed three minutes later by Carrick's sublime opener. It was the crucial goal that on many recent European nights had evaded Sir Alex Ferguson's team and sent them out of the competition; on this occasion it served as the catalyst for a phenomenal passage of play that ensured their progression.
In the 17th minute Smith was rewarded for his industry up front when a Gabriel Heinze pass towards the centre of the field was completely missed by Cristian Chivu in a moment of madness and the blonde striker finished coolly from 18 yards. It evoked memories of his winner in the Stadio Olimpico for Leeds United against Lazio back in 2001; if possibly not for ardent Red Devils fans.
Only two minutes afterwards the score was 3-0 as Smith played in Ryan Giggs, who had popped up on the right wing. Attacking the by-line, he fed the ball to the edge of the six-yard box where Rooney had made a run to meet it and hit the back of the net via the inside of the far post.
Still, at that point two goals for the second-placed Serie A side would have put them through and so it was important that the Premiership leaders, beaten by Portsmouth in the league at the weekend, balance attack with defence. They achieved that as Mancini and Totti were frustrated and Montenegro international Vucinic barely got a kick in the final third.
Emotions boiled over at one stage in the first half when Smith was booked for a late tackle on Chivu and then felt wronged when Marco Cassetti was not punished for a blatant off-the-ball kick, while Rio Ferdinand was also shown a yellow card. The fourth goal arrived two minutes before the break when Ronaldo, along with Giggs a constant threat on the counter, bore down on the penalty area and smashed a low shot inside the near post.
The Giallorossi had another nightmare start to the second period when Carrick, who worked tirelessly off the ball throughout the match, passed to the veteran Welsh wing wizard on the left. He low first-time cross was left by Smith and missed by Doni before Ronaldo stuck it away for an incredible fifth goal to pep up the atmosphere once more.
The scenes of jubilation in the stands were the main show from that moment on as Roma struggled to break down a dense United defensive unit; until Carrick took possession from Heinze around the hour mark. He opened up his body and picked out the far top corner with another goal of the very highest quality. Smith attempted an outrageous chip on the bouncing ball from the corner of the box which landed on the roof of the net before Totti crossed to De Rossi, who turned in a volley from ten yards that on another occasion would have had the Italian fans shouting the house down.
Alas for them it meant absolutely nothing in the circumstances and Evra even cancelled it out with a cracking low shot inside the near post from the right with his natural left foot as Doni anticipated a drive to the far upright!!
Totti tried his utmost to score in a match that he described beforehand as more important than last summer's World Cup final victory for Italy over France, though whether he feels the same way now it has ended in such a way is debatable.
Manchester United were deserved winners, Roma swept away by their attacking ferocity early on – perhaps something lacking in recent seasons of failure in Europe.
Manchester United: Van der Sar, Brown, Ferdinand, Heinze, O'Shea (Evra 52), Ronaldo, Fletcher, Carrick (Richardson 73), Giggs (Solskjaer 61), Rooney, Smith.
Subs Not Used: Kuszczak, Dong, Cathcart, Eagles.
Booked: Smith, Ferdinand.
Goals: Carrick 12, Smith 17, Rooney 19, Ronaldo 44, 49, Carrick 60, Evra 81.
Roma: Doni, Panucci, Mexes, Chivu, Cassetti, Wilhelmsson (Rosi 88), De Rossi (Faty 86), Vucinic, Pizarro, Mancini (Okaka Chuka 90), Totti.
Subs Not Used: Curci, Defendi, Ferrari, Taddei.
Booked: Cassetti, Mexes.
Goals: De Rossi 69.