FULL-TIME: ARSENAL 2-0 FC PORTO

Gallas is replaced by Alexandre Song. The injury doesn't look too bad and he is able to walk back to the bench

Gallas has gone down injured with no-one near him. Arsenal are short-handed at the back as he recieves treatment off the field.

Rosicky releases Ljungberg on the left, but the Swede's aimless cross is nodded back to the goalkeeper.

Gilberto is shown a yellow card for a foul on Meireles in the centre circle.

Theo Walcott receives a rapturous reception as he comes on for Hleb.

Eboue and Henry combine well to create a chance for Ljungberg. The Swede is unwilling to use his left foot, and by the time he turns back on to his right the Porto defence have recovered and his shot is blocked.

Quaresma ghosts beyond Eboue and cuts in from the left flank before unleashing a low shot which Lehmann gathers at the second attempt.

It's almost 3-0 as Henry bamboozles Bosingwa on the right before cutting the ball back for Fabregas, but the Spaniard's shot is straight at the goalkeeper.

Ljungberg attempts to jink his way through the visiting defence but only succeeds in losing possession.

Van Persie is replaced by Ljungberg.

Quaresma shows some neat skills before firing over a cross from the Porto left. His centre is too deep and runs behind for a goal-kick.

Bosingwa does well to get past Gallas and put over a cross, but Lehmann claims it with ease.

Fabregas goes down in the area looking for a penalty. The referee, correctly, waves play on.

Porto make their final change as Adriano replaces Anderson.

Rosicky is booked for what appears to be a perfectly executed sliding tackle on Jose Bosingwa. An extraordinary decision by the Italian referee.

A rare Porto attack finishes with an on-target shot from Meireles, but it's a simple save for Lehmann.

The Gunners are well on top but need to be careful they don't leave themselves open at the back as they go forward in search of a third.

Arsenal win another corner. The delivery arrives at Rosicky's feet, but his shot sails high into the stands.

Porto clear the flag-kick and Anderson surges forward to the edge of the Arsenal box before being brought down by Hoyte. The free-kick comes to nothing.

Henry's pace and movement are causing the Porto defence all kinds of problems now and he wins a corner.

Porto look to hit back quickly but a back-tracking Henry dispossesses Meireles on the edge of the Arsenal box.

ARSENAL 2-0 FC PORTO Gallas carries the ball through midfield and lays it off to Henry on the edge of the Porto box. The skipper squares it to HLEB, who smashes a low shot beyond the keeper. A fantastic goal.

Porto made a double change at the break, with Lisandro Lopez and Raul Meireles replacing Postiga and Ricardo Costa.

Arsenal get the second half underway.

HALF-TIME: ARSENAL 1-0 FC PORTO

The lively van Persie almost gets the goal he deserves with a looping header which Helton struggles to scramble clear.

Fabregas loses possession in midfield and is relieved to see Toure get across to the right flank to clear the ball and halt the resulting attack.

Arsenal, full of confidence after the goal, knock the ball about nonchalantly in midfield, until van Persie shoots from the edge of the box, only to see his effort blocked.

ARSENAL 1-0 FC PORTO Eboue breaks down the right and puts over a superb out-swinging cross which HENRY heads across the goalkeeper and into the far corner.

Van Persie, this time on the left, beats the full-back only to see his cross blocked.

A beautiful cross-field pass from Hoyte picks out van Persie on the right wing. The Dutch striker cuts into the box and hits a low shot, which is destined for the bottom corner until Helton gets down to make a good save.

The resulting free-kick is headed clear as far as Cesc Fabregas, who smashes a shot from 25 yards only to see it fly inches over the bar.

Ricardo Costa picks up the first booking of the night for a foul on Hleb.

Great play from Henry who picks out van Persie in space in the Porto box. The Dutchman snatches at his shot and sends the ball over the bar. A real waste.

Emmanuel Eboue puts over a dangerous cross from the right, but Arsenal's forwards can't react quickly enough as the ball flies across the area.

Rosicky makes a textbook sliding tackle in midfield, but a theatrical tumble from Anderson fools the referee into awarding a free-kick.

Arsenal force a corner but van Persie hits the ball over the men in the middle and out for a goal-kick.

Arsenal pass their way through midfield, with Gilberto Silva, Rosicky and Hleb involved. The ball eventually reaches van Persie on the left, but Helton is able to intercept his cross.

Lehmann comes past the penalty spot to try and claim a corner, but misses the ball. Porto are unable to capitalise.

Quaresma wins the ball in midfield and attempts to release former Spurs striker Helder Postiga. Fortunately for Arsenal his throughball runs through to Lehmann.

Porto have managed to wrest control of midfield from Arsenal and it is now Wenger's side who are chasing round in search of a touch of the ball.

William Gallas concedes a needless corner and it almost proves costly as Jens Lehmann is forced to hack away Ricardo Costa's flicked shot.

Ricardo Quaresma tries his luck from 30 yards, but the former Barcelona midfielder's shot is embarrassingly high and wide.

Arsenal have started impressively and Porto have hardly touched the ball so far.

Hleb and Rosicky combine well on the right flank, but the Czech's cross fails to pick out Thierry Henry.

A typically slick passing move from the hosts sees Hleb, van Persie and Tomas Rosicky combine, before the Czech midfielder hits a shot from 20 yards straight at the goalkeeper.

Porto win a free-kick 30 yards out, but Anderson's delivery is poor and easily cleared by the home defence.

Kolo Toure bundles the ball home from the corner, but the linesman rules the ball went out before reaching the Ivorian.

Van Persie breaks from midfield and tries his luck from distance, forcing Helton to push it away for a corner.

Arsenal's first attack of the game finishes with a poor cross from van Persie, but a visiting defender puts it out for a corner.

Porto get the game underway.

Arsenal have suffered a late setback, with Johan Djourou picking up an injury in the warm-up. Justin Hoyte comes into the starting line-up.

Porto, who won the trophy in 2004, began their campaign with a 0-0 home draw against CSKA Moscow, so need to take something from tonight's game.

CSKA Moscow have beaten Hamburg 1-0 in tonight's other Group G match. It's the German side's second loss after they went down 2-1 to Arsenal on matchday one.

Emmanuel Adebayor and Freddie Ljungberg drop out of the side which beat Sheffield United at the weekend, with Aleksandr Hleb and Robin van Persie replacing them.

Arsene Wenger has made two changes to his starting line-up for Arsenal's first home game of their Champions League Group G campaign.