Source: Telegraph
Rio Ferdinand the key for Manchester United
Cristiano Ronaldo's incredible sixth minute goal, an unstoppable strike from 40 yards, earned a 1-0 victory in Estadio do Dragao and booked an all-English semi-final tie against Arsenal.
But England defender Ferdinand produced one of his most outstanding displays of the season at the back to help steer the European champions past Porto, who had emerged from the Old Trafford first-leg with a 2-2 draw last week.
With Ferdinand sidelined with a groin injury suffered on international duty earlier this month, United conceded five goals in three games against Aston Villa, Porto and Sunderland.
But Ferguson admitted that his return against Porto alongside defensive partner Nemanja Vidic gave United the platform from which to record a famous victory.
Ferguson said: "There was a real difference to our performance in the first-leg, but Rio's return really laid the foundations for us.
"He has been a great part of our success this season alongside Vidic and I have to say that Porto never looked like scoring.
"We had been leaking too many goals for a few weeks, but we looked like we are back to the mindset of not giving goals away again.
"After what happened in the first-leg, it was always going to be a bit of a battle to get the win in Porto, so it's a great result for us."
United became the first English team to beat Porto on their own ground by eliminating Jesualdo Ferreira's outfit.
The hosts had previously gone unbeaten in eleven games at home to English opposition, but United midfielder Michael Carrick, who overcame a first-half ankle knock to play a key role for Ferguson's team, insisted that United always believed they could end Porto's proud record.
Carrick said: "Obviously it's a tough place to come and get a result, but we knew it was in our hands.
"We really fancied ourselves to come and score here and defend right. It was a good team performance all round and we're delighted to go through.
"To get the early goal was a big bonus and from then on, I thought we were in control.
"They came at us, which you'd expect, but we defended very well, even though it was still on a knife-edge.
"From going through, all of a sudden you can be going out, so we were well aware of that and knew we had to defend right to the final whistle. I thought we did that very well."
