Sir Alex Ferguson will have felt like raising a glass of Oporto's most famous tipple after seeing his Manchester United side claim that all-important top spot in Group A.

Normally Ferguson prefers a fine red wine, but in the home of port he might well have been tempted by a wee glass of the local tipple to celebrate United's achievement.

And well he might because this impressive victory means United will avoid favourites Real Madrid in Friday's quarter-final draw in Nyon.

Ferguson was anxious to give the eight-time European Cup winners a wide berth, at least until the final in Hampden Park - the shrine as he reverentially calls it.

However, Ferguson might not be so enthralled by the thought that he has a 3/1 chance of meeting Liverpool, who have won their last five matches against United, in the quarter-finals following the Merseysiders' win over Roma.

What was only United's third away win in 15 Champions League games had not been in doubt from as early as the 14th minute when Laurent Blanc gave them the lead.

United smoothly moved up through the gears and Ole Gunnar Solskjaer made it 2-0 with a real poacher's effort before David Beckham fired home a penalty to chalk up United's biggest European away win since their 3-0 win over Sturm Graz in September 1999.

Even without the injured Roy Keane, Juan Sebastian Veron and Ruud van Nistelrooy, United were far too quick and slick for Boavista.

And remember this was against a Boavista side who had been unbeaten in their previous seven Champions League home games and had conceded just three goals in the last five of those.

United picked up where they had left off at West Ham on Saturday and they opened the scoring on 14 minutes in the compact Estadio do Bessa.

Beckham sent over a corner from the right and Blanc capitalised on some slack Boavista defending to side-foot home unchallenged from around eight yards out.

It was the Frenchman's third goal for United and ironically his first since he netted in the 3-0 win over Boavista at Old Trafford back in December.

Diego Forlan, who made his first Champions League start, thought he had finally opened his United account midway through the half when he met stand-in skipper Ryan Giggs' cross with a diving header only for Ricardo to block his effort.

Boavista briefly rallied and Erwin Sanchez hit a curling right-foot shot, which Fabien Barthez touched round his left-hand post.

The game was beginning to open up and Beckham fluffed a great chance to double United's lead.

Ricardo parried Forlan's right-foot shot and the ball fell invitingly to Beckham, but with the goal at his mercy the England skipper embarrassingly sliced his effort wide.

United threatened again and Forlan crossed from the left for Solskjaer to head over.

The Norwegian was disappointed with himself, but he need not have worried and in the 29th minute he scored his 19th goal of the season to equal his best-ever haul for United.

Giggs was the instigator and he pierced the Boavista defence to play a one-two with Beckham, and when Ricardo failed to hold his shot, Solskjaer reacted first to knock the rebound into the net.

United were now almost scoring at will and on 51 minutes they made it 3-0 from the penalty spot.

Solskjaer found Nicky Butt on the left and he laid the ball inside to send Scholes bursting into the box and as he did Martelinho caught his heel.

In the absence of van Nistelrooy, Beckham rifled home his second penalty in successive games for his 15th goal of a most prolific season.

With victory assured United made three changes, including Michael Stewart who came on to make his Champions League debut.

However, they were reduced to 10 men 15 minutes from time when Solskjaer hobbled off injured.

Not that it mattered, and even with 10 men United were still the better side.

United's Champions League rivals, including Real, take note.

Teams

Boavista: Ricardo, Frechaut, Turra, Pedro Emanuel, Soares da Silva (Martelinho 34), Loja, Petit, Silva (Goulart 21), Sanchez, Duda, Serginho, Goulart (Marcio Santos 59).

Subs Not Used: Khadim, Avalos, Pedro Santos, Jorge Couto.

Booked: Martelinho, Pedro Emanuel.

Man Utd: Barthez, Gary Neville, Blanc (O'Shea 73), Johnsen (Phil Neville 73), Silvestre, Beckham, Butt, Scholes (Stewart 59), Giggs, Solskjaer, Forlan.

Subs Not Used: Carroll, Irwin, Fortune, Djordjic.

Goals: Blanc 14, Solskjaer 29, Beckham 51 pen.

Ref: Konrad Plautz (Austria).