When Porto rolled up at Old Trafford in the Champions League, few expected the Portuguese side to pose much of a threat to a United side chasing an unprecedented quintuple of trophies this season. Within four minutes though fears began to creep in as Porto took a lead through Rodriguez, thanks to mistakes from Cristiano Ronaldo and Johnny Evans.

United were level with quarter of an hour played courtesy of a mistake by Bruno Alves. Wayne Rooney brilliantly anticipated a back pass to the keeper and stepped in to intercept Alves’ loose ball and calmly chipped it over the advancing Porto keeper, Helton.

It proved only light relief though as United were subjected to wave after wave of Porto attack, producing only fleeting glimpses of the talent we all know exists in the Old Trafford side. Carlos Tevez gave United the lead with five minutes to go after he turned in Rooney’s clever flick from a throw and it looked like United had dodged a bullet and would take a, frankly undeserved, lead into the second leg. However, with just a minute of normal time left, the Argentine Mariano Gonzalez found himself unmarked at the far post and latched onto Lopez’s cross to bury the ball into the back of the net.

The result leaves United with an uphill struggle for the second leg in Lisbon, needing to win the tie or score more than two goals in a draw if they are to progress to the semi-final stage.

Arsenal fared slightly better on their trip to Villareal. The Spanish side have never lost to English opposition on home soil and it looked as if they were going to see-off a below-par Arsenal after they dominated the opening 45 minutes. After just 10 minutes Marcos Senna, one of Spain’s European Championship heroes, launched an unstoppable shot from over 30 yards out and beat the flailing Manuel Almunia to hand the Yellow Submarines the lead. Things got worse for the Gunners at the Estadio El Madrigal as Almunia and then William Gallas were forced off early with injuries and it seemed as if Villareal would be heading to the Emirates with an advantage.

Arsenal underwent something of a revival in the second half and after a period of increased pressure they got the equaliser they deserved. Cesc Fabregas, who was constantly booed by the Spanish crowd, clipped a ball into the penalty area which Emmanuel Adebayor took on his chest before hitting an audacious overhead kick into the corner of Diego Lopez's net. It was no more than Arsenal deserved and despite their best efforts they couldn’t force the winner. However, they will fancy their chances of progressing to the semi-finals after their display in Spain and backing the London side may be a piece of handy football betting, while Manchester United may be left to rue their defensive lapses when they travel to Lisbon in eight days' time.