LONDON, April 10 (Xinhua) -- Manchester United booked their berth in the UEFA Champions League semi-finals after a devastating7-1 win over Roma at Old Trafford on Tuesday.

    Goals from Alan Smith, Wayne Rooney, Patrice Evra, and a double each by Michael Carrick and Cristiano Ronaldo saw Sir Alex Ferguson's side win the tie 8-3 on aggregate.

    At Mestalla, Michael Essien's 90th minute strike saw Chelsea defeat Valencia 2-1 and join the United in the semis on an 3-2 aggregate victory.

    The Old Trafford side overturned a 2-1 first-leg deficit in style to set up a last four meeting with either Bayern Munich or Milan.

    Three goals in an eight-minute burst early in the first half sent the hosts into a dreaming start.

    Carrick opened the scoring on 12 minutes, bending the ball home from 25 yards.

    The Red Devils extended their lead only five minutes later, with Smith knocking the ball home to put the finishing touches on an exquisite move by Gabriel Heinze and Ryan Giggs.

    The Italians' defence fell into complete collapse on 17 minutes when Rooney added a third for the United, timing his run superbly to slot home Giggs' low cross.

    Ronaldo made it 4-0 before half-time with a precise finish into the bottom corner. And the Portuguese, in sublime form, did not give the Italian a break in the second half as he slid home a low Giggs' cross before Carrick's piledriver made it 6-0 on the hour mark.

    Roma did get one goal back through De Rossi's neat finish on the turn but the United restored their six-goal margin when substitute defender Evra's low shot beat Doni.

    It was the biggest winning margin in a Champions League knockout round and Roma's heaviest defeat in Europe.

    "It was our best ever, a fantastic performance by every one of our players," said Ferguson after the match.

    "We showed great confidence after two defeats in the last week. All great teams get over these mishaps and we did that tonight," he added.

    Michael Essien scored in the last minute to break Valencia's hearts in the Mestalla.

    The midfielder drilled the ball past Santiago Canizares at the near post with seconds remaining to send the traveling fans into delirium.

    Fernado Morientes handed Valencia the lead on 32 minutes when he slid home a left-foot shot from a Joequin's cross.

    Chelsea did not let their heads drop and Andriy Shevchenko levelled from close range before Essien won it late on.