Ji-Sung Park fired Alex Ferguson's team upfront early on eight minutes, and Cristiano Ronaldo scored either side of the interval to dent Arsenal's hopes of making a comeback.

The international ace hit the second in the 11th minute, and deepened the Gunners' misery again on 61 minutes.

Robin van Persie notched Aresnal's sole goal from the spot 18 minutes from the final whistle.

The second finalists will be determined on Wednesday, when Chelsea clash with Barcelona at Stamford Bridge.

Fiery Start

Arsenal were aiming to snatch an early opener to cancel out United's slender lead, which was earned by John O'Shea's winner in the first leg.

But their pressure from the left flank in the early minutes didn't pay dividends, and the defending champions soon demonstrated their out-and-out superiority.

Park set the game on fire and hit a surprising opener when his marker Kieran Gibbs slipped in the area to allow the South Korean to slide home after latching onto Ronaldo's precise low cross.

Few minutes later, Portuguese virtuoso Ronaldo doubled the lead from a tight angle after cunningly converting a free-kick that went inches past Manuel Almunia's fists.

Afterwards, United tightened their grip on the game, while Arsenal kept trying in vain to reduce the arrears through conservative attempts from both wings.

On 18 minutes, Wayne Rooney could have netted a third goal, but Almunia parried his curling shot away at full stretch.

Almost on the half-hour mark, Ronaldo tried his luck with a tame shot, but the Spanish keeper competently blocked it.

The hosts got relatively energized late in the first half, but couldn't carve out any clear-cut chances.

Shy Attempts

As in the first period, Arsenal came on with all guns blazing after the restart, but barley threatened their opposition.

United took a stranglehold on the match again, despite the useless pressure of the home side.

Ronaldo finished off a sweeping counter attack when he outran his marker and diverted Rooney's inch-perfect low cross into the net, to leave Arsenal with no hope at all.

On 72 minutes, Arsenal substitute Nicklas Bendtner skillfully penetrated United's area with nice dribbling, but his drive hit the side-netting.

Quarter hours from time, Van Persie scored the consolation goal upon converting a penalty-kick.

The referee adjudged Darren Fletcher to have fouled influential midfielder Cesc Fabregas in the area, and also sent off the Scots for his roughness.

Consequently, Fletcher has been ruled out of the final through automatic suspension.

Arsenal slightly improved after pulling one back, United kept the upper hand though.

Fabregas squandered a golden chance on 86 minutes from point-blank range, with both sides' players flailing in the box in a set-piece competition.

The game's tempo evidently slowed down in the dying minutes, and United went through on a 4-1 aggregate win.

Watch the game's goals