Below-par Arsenal slumped to defeat last night to leave themselves with a tougher path towards Champions League glory.
With his side already qualified for the last 16 and with several key men – like captain Cesc Fabregas and striker Robin van Persie – carrying injuries, manager Arsène Wenger felt confident enough to take a calculated gamble with his team selection against a well-organised Portuguese outfit, who had never lost here to an English side a European tie.
However, the move backfired as the much-changed Gunners never really got going and were undone by goals either side of the break by Bruno Alves and Lisandro Lopez.
Arsenal will now be drawn against one of the group winners next Friday – which include Juventus, Bayern Munich and Barcelona – and so must play the second leg away from home if they are to make the final in Rome.
It was a bright start by the Gunners. After five minutes, the Mexican teenager Carlos Vela drew a foul out on the left. Denilson sent in a deep free-kick, which Diaby headed over.
At the other end, Emmanuel Eboué was penalised for running across Hulk as the striker charged towards the Arsenal penalty area.
The free-kick, some 25 yards out, just to the left of the arc, was taken by Alves and Manuel Almunia had to get down to his right to make a smart save.
Another real chance opened up for the visitors on 25 minutes when Nicklas Bendtner, this week in bright green boots, fed Aaron Ramsey on the right edge of the Porto box. The young Welshman turned his marker and fired in a low, angled shot which Helton did well to push around the far post.
Almunia came to Arsenal's rescue when he blocked Lucho Gonzalez's close-range effort and William Gallas hacked the loose ball clear. Space opened up again in front of the Arsenal box on 33 minutes, this time Raul Meireles drilled a 20-yard strike just wide.
It was no surprise when the home side took the lead six minutes before the break. A corner from the left was floated into the Arsenal box, and Alves arrived in front of Abou Diaby at the far post to head past Almunia.
Arsenal, who only needed a point to secure top spot, stepped up a gear as they tried to get back on level terms before half-time. However, their delivery into the danger area was poor as the Porto defence stood firm. The visitors were soon further behind in the 54th minute. Arsenal gave possession away in midfield, with Fernando picking up the ball and feeding it through to Lisandro at the edge of the box. The striker made no mistake, smashing his shot into the top right corner.
Arsenal again looked to make an immediate response, with Ramsey's neat turn and shot testing Helton. Wenger made a double change on 59 minutes, when youngster Kieran Gibbs replaced Diaby and 16-year-old Jack Wilshere for Ramsey.
It would have been all over for the Gunners had Cristian Rodriguez not pulled his angled shot wide when played in on the overlap down the left. As it was, there remained hope of a comeback and slowly Arsenal mounted some pressure.
However, Rodriguez almost got clear of Eboué as they raced towards the Arsenal goal, but the defender did enough to pressurise the striker into a shot off target. Lucho dragged his close-range shot wide as the Gunners were exposed at the back once more.
Arsenal were awarded a free-kick just outside the box, but Bendtner's low shot beat the wall, the Porto keeper collected it comfortably – which just about summed up a lacklustre display from the Gunners.
FC Porto: Helton, Fucile, Rolando, Bruno Alves, Pedro Emanuel, Lucho Gonzalez (Costa, 77) Fernando, Raul Meireles, Lopez, Hulk (Guarin, 88), Rodriguez (Mariano Gonzalez, 78). Substitutes not used: Nuno, Stepanov, Lino, Sektioui.
Arsenal: Almunia, Eboue, Gallas, Silvestre, Djourou, Ramsey (Wilshere, 59), Diaby (Gibbs, 59), Song Billong (Randall, 78), Denilson, Vela, Bendtner. Substitutes not used: Fabianski, Hoyte, Merida, Simpson.
Referee: K Vassaras (Greece)Reuse content