United will face Arsenal in an all-English Champions League semi-final, after the Reds became the first English team to beat Porto in the Estadio do Dragao.
It took something special: a quite breathtaking 40-yard strike from Cristiano Ronaldo which, allied to a first clean sheet in six games, took the holders into the final four. Indeed, it would have been the Reds' defensive resolve which would have pleased Sir Alex Ferguson most, as the return of Rio Ferdinand brought an assuredness to the champions and restricted the dangerous hosts to but a handful of opportunities.
Following last week's 2-2 first-leg draw, Porto went into the match with a crucial away-goal advantage. That was tellingly overturned inside six minutes of an imposing second encounter. Had Sir Alex been asked to draw a blueprint of his perfect start, it wouldn't have been too far removed from what actually transpired.
The Reds were already looking confident when Anderson slipped a pass to Ronaldo, but the winger's ambition beggared belief. Having received the ball just inside the hosts' half, Ronaldo took a touch to set himself and arrowed an unstoppable effort into Helton's top corner. The ball travelled 40 yards to the goal, but the Brazilian goalkeeper could get nowhere near it.
A Sporting Lisbon export, Ronaldo was predictably jeered from the first whistle by the blue and white clad hordes in the stands. Suddenly, he had provoked silence on every side of the Estadio do Dragao - bar, of course, the sizeable pocket of writhing, jubilant United fans behind the opposite goal.
The Reds' approach to the game mirrored that of Porto in the first leg: dominant, with the hosts completely on the back foot. Indeed, it took 20 minutes for the Portuguese champions