Ronaldo's powerful 40-yard strike proved too hot too handle for keeper Almunia
By Phil McNulty
Chief football writer at the Emirates
Manchester United produced a virtuoso display to remain on course to become the first team to retain the Champions League - and destroyed Arsenal boss Arsene Wenger's dream of winning his first European trophy.
Arsenal's hopes of wiping out a single-goal deficit from the first leg ended inside 11 minutes as United struck twice to silence an expectant crowd at the Emirates.
Ji-Sung Park pounced on Kieran Gibbs' slip for a close-range finish after eight minutes, while Cristiano Ronaldo fired a 40-yard free-kick past startled keeper Manuel Almunia three minutes later.
It left Arsenal's plans, plus Wenger's bold promise of a "magnificent" performance from his players, in tatters as they were simply unable to cope with the power, pace and energy produced by Sir Alex Ferguson's side.
Ronaldo's second goal of the game after 61 minutes summed up his side's display in the space of a few devastating seconds.
Arsenal were undone from their own corner by a superb sweeping move that also involved starring roles for Park and Wayne Rooney before Ronaldo completed the formalities with a flourish. It rubber-stamped United's passage into a final against Chelsea or Barcelona in Rome on 27 May - and on this evidence they will take some stopping.
The only blot on United's otherwise perfect night came 16 minutes from time when Darren Fletcher was sent off by referee Roberto Rosetti, who ruled the midfielder had fouled Cesc Fabregas as he raced in on goal.
Robin van Persie's penalty will not cause United as much pain as Fletcher's suspension for the final.
If United's first-leg performance did not bring the margin of victory it deserved, they were full value for this triumph.
And as Ferguson and United's players celebrated, Wenger was left to contemplate the stark statistic that Arsenal have not won a trophy since they beat these same opponents in the 2005 FA Cup final - and looked light years behind them on the evidence of these two games.
Early goals killed off game - Ferguson
United will now press on to try to seal another Premier League title, safe in the knowledge they can take a tilt at winning this European trophy for the fourth time.
Arsenal attempted to crank up the atmosphere inside the Emirates by placing thousands of flags on seats around the stadium but two early blows from United ensured they were swiftly lowered.
United were desperate for the away goal that would leave Arsenal facing a mountainous task and they were gifted it via an error from Gibbs. He looked comfortably positioned to clear Ronaldo's routine cross but he slipped and Park was on hand to take advantage by sliding in to lift a finish over Almunia.
Arsenal's plight became virtually impossible three minutes later when another mistake, this time from Almunia, allowed United to double their advantage and leave the Gunners requiring four goals.
Van Persie fouled Ronaldo 40 yards out and while his strike was sweetly-struck and dipping, Almunia must take responsibility for moving too late to save an effort that arrived at a comfortable height.
Arsenal's players - and their thousands of followers - were visibly shell-shocked and Rooney almost made it three after 18 minutes.
Wenger disappointed with manner of display
Playing with great discipline in a left-flank role, he cut in dangerously to test Almunia with a shot the keeper was just able to turn to safety.
United were in complete control and Ronaldo was just off target with a header from Anderson's resulting corner.
Arsenal had been dominated to such an extent that they were reduced to ignoring Wenger's long-held philosophies as they launched aimless balls in the direction of Emmanuel Adebayor and Van Persie.
Their only response was a tame header from Fabregas that provided little more than catching practice for Edwin Van der Sar.
If Arsenal hoped the interval would inspire some remarkable transformation in a one-sided encounter, they were to be disappointed as United simply resumed with the same air of superiority.
Ronaldo tested Almunia with a low shot at his near post before he added United's third - a goal that summed up the quality of his side's performance.
From an Arsenal corner, Ronaldo found Park just 20 yards from his own penalty area. He played in Rooney and when he served up a perfect pass, there was Ronaldo to complete a picture goal with a finish high past Almunia.
Ferdinand would not swap Man Utd players
It afforded Ferguson the luxury of being able to remove Rooney and Patrice Evra, players who would have missed the final had they had picked up another yellow card.
Fletcher did, however, suffer that fate when he was shown a straight red card by referee Rosetti 14 minutes from time when Fabregas tumbled as the pair collided in the penalty area.
Rosetti awarded a penalty, which Van Persie duly scored, but replays showed Fletcher appearing to get a clean touch on the ball before Fabregas fell to the ground - although there was no suggestion the Arsenal captain dived.
United then simply played out time before taking deserved acclaim at the conclusion of a magnificent team effort - as Europe's elite trophy came into sight for Ferguson and his men once more.
Arsenal: Almunia, Sagna, Toure, Djourou, Gibbs (Eboue 45), Walcott (Bendtner 63), Fabregas, Song Billong, Nasri, Van Persie (Vela 79), Adebayor. Subs Not Used: Fabianski, Silvestre, Diaby, Denilson.
Booked: Nasri, Adebayor, Eboue.
Goals: Van Persie 76 pen.
Man Utd: Van der Sar, O'Shea, Ferdinand, Vidic, Evra (Rafael Da Silva 65), Fletcher, Carrick, Anderson (Giggs 63), Park, Ronaldo, Rooney (Berbatov 66). Subs Not Used: Kuszczak, Evans, Scholes, Tevez.
Sent Off: Fletcher (75).
Goals: Park 8, Ronaldo 11, 61.
Ref: Roberto Rosetti (Italy).
BBC Sport Player Rater man of the match: Man Utd's Cristiano Ronaldo (8.67 on 90 minutes).
Please note that you can still give the players marks out of 10 on BBC Sport's Player Rater after the match has finished.
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