Arsenal 1 - 3 Man Utd: (United win 4-1 on aggregate) - United march on Rome after brutal rout of Arsenal

LIKE the great Emperors of the past, Sir Alex Ferguson will attempt to rule Rome in three weeks' time after Manchester United produced an awesome attacking display to destroy Arsenal.

A fortuitous opener from Park Ji-sung was followed by a thunderous 40-yard free-kick from Cristiano Ronaldo to effectively book a Champions League final date with Chelsea or Barcelona on 27 May after only 11 minutes.

Ronaldo capped a fine performance and drew howls of glee from David Beckham, who had made the trip from Milan to witness a victory that will go alongside that staggering win over Juventus in 1999 which the former England captain was a part of, by sliding home a third goal, his 25th of the season.

It was not quite a perfect night for United. How could it be when Darren Fletcher ended it in disbelief at the red card for a tackle on Cesc Fabregas which will rule the Scotland midfielder out of the final?

However, it was not far off, leaving United to await events at Stamford Bridge tonight with so many neutrals, if not a Chelsea side hell-bent on revenge, hoping Barcelona set up what would be a dream decider.

No amount of meticulous planning can legislate for bad luck. It is the unknown factor that, in an instant, can screw any amount of hopes and dreams into the tightest ball and throw them out of the highest window, never to be seen again.

Kieran Gibbs has not been a first-team regular very long. Fitness permitting, he has almost a decade and a half in front of him in the Arsenal side.

It is a fair bet, at the end of his career, the 18-year-old still regards the horror that unfolded eight minutes into what was such an eagerly awaited contest as the worst moment he had to endure. In his head, Gibbs was about to control Ronaldo's cutback, then decide whether to play a short pass out of defence or present goalkeeper Manuel Almunia with a routine clearance. Fate had other plans.

Instead, poor Gibbs lost his footing and hit the ground with a thump. Like lightning, Park seized on the loose ball, delicately lifting it over Almunia, whose arrival came just too late.

The United contingent went delirious. Fans, coaches, manager, players, Beckham alike all knew what it meant. They knew the prospect of Arsenal getting three goals to go through was so remote to be beyond comprehension.

But if United's opener came courtesy of good fortune, their next was the result of audacity, mixed with high ability.

To even think of going for goal from the spot when Robin van Persie had clattered into Ronaldo would be dismissed by most professionals as foolhardy.

Yet, in Porto three weeks ago, the world player of the year drove home a shot measured at exactly 39.1 yards. As Ronaldo stepped back and waited from even further out, ready to unleash his missile, Almunia knew what to expect.

Indeed, it could be argued that from such distances no goalkeeper should be beaten. But as Ronaldo let fly, with venom, and watched his shot dip and flicker, Almunia was powerless to prevent it ripping into the net.

Ronaldo, though, moved to absolve the keeper of any blame for the goal after the game.

"The shot was quite difficult to save because the ball moved a little bit," he said. "I just try to do my best to put the ball in the net and it was a good goal."

The Portuguese has not enjoyed the same consistency of last season, but he is convinced he is returning to form at exactly the right time as United home in on domestic and European titles.

When asked if he is now back to his best, the attacker said: "I think so, yes.

"In the last few games I have felt good, felt fit. This is a crucial time in the season and the best games are coming."

If three goals had been unlikely, four were an impossibility, turning the remaining 79 minutes into an extended wake, leaving Arsene Wenger on the bench wondering what had hit him, knowing his Champions League obsession would not end in Roman triumph.

In fairness, Arsenal tried to rally. It was just that by pushing forward, they left wide-open gaps that United are too experienced to ignore.

Almunia's fingertips denied Wayne Rooney, Ronaldo's header from the corner whistled wide, then two more free-kicks from the latter were saved. When the Portuguese player cut inside Emmanuel Eboue, on as a half-time replacement to put Gibbs out of his misery, the shot would have found the bottom corner had Almunia not denied him.

There was nothing the Spaniard could do when United attacked again, Ronaldo supplying the finish to Rooney's cross.

As his players cavorted in glee, Ferguson ordered them to tone down their celebrations out of respect to the hosts.

It was the only mercy they showed all night, although for Fletcher there was a nasty sting in the tail.

The Scotland international got studs on the ball before sending Fabregas flying in the penalty area, earning him a red card as costly as it was unjust.

Netherlands international Van Persie impressively converted the spot-kick – but it was little consolation for Arsenal.