Into the final minute and there is no added time to be played.

Vela does superbly on the left and his cutback finds Eboue, who hits the base of the post from a matter of a few yards out.

Bendtner sets up Adebayor for a hat-trick, but the Togo striker somehow fires his shot just wide of the far post when clean through.

Arsenal are coasting to a comfortable victory and must be fancied to go a long way in the competition this season.

Bendtner lifts the ball back across the area, Adebayor turns it on, but Vela is beaten to the ball and Porto clear the danger.

A little over ten minutes to play and Porto must be praying for the final whistle.

Costa gains possession over on the left and fires a right-foot drive a yard wide of the far post from a full 35 yards.

Vela dribbles past a couple of defenders, but cannot get a shot in and Bendtner manages to send the ball out for a throw-in.

Adebayor's second of the evening has definitely wrapped up the victory, if there was any doubt in any case.

PENALTY to Arsenal, as Guarin is penalised for a challenge on Bendtner.

Rodriguez counters for Porto, drifting inside from the right and smashing a 30-yard left-footer narrowly over the top.

Fabregas feeds the overlapping Eboue, but his cross is deflected up into the air and Helton gathers.

Midway through the second half and the Gunners look so comfortable.

Helton spills a 20-yard fizzer from Fabregas and Adebayor is unable to turn the rebound home and Porto clear the danger.

Sagna gets a good cross in from the right, but Adebayor slices his shot wide of the near post.

Fabregas and Nasri open up the Porto defence again, but Walcott is caught just offside.

Nasri drives forward down the centre and his rasping drive from all of 35 yards is parried away by Helton.

An hour played and Arsenal are in total command and have a valuable win in the bag.

Porto are on the ropes now and could concede a few more yet.

Walcott races clear down the right and eventually plays the ball in for Nasri to score, but he screws the ball wide of target from close range.

This could turn into an exhibition now, as Denilson fires a shot over the top from 25 yards out.

It should have been four, Kolo Toure drills the ball across the area and Walcott somehow turns the ball wide from less than six yards out.

Wenger looks far more relaxed on the bench now and so he should.

Walcott lifts a ball to the far post from the right and Cristian Sapunaru turns the ball behind for a corner, which comes to nothing.

That goal has killed the game off totally.

Porto get the second period underway.

Porto threaten with a superb counter-attack, but Gallas reads the danger and gets across in the nick of time to clear up the situation.

Guarin does well on Porto's left flank and gets the ball into the area, but Clichy guides it back to Almunia.

That second goal has given Arsenal a big cushion for the second half.

Walcott races away down the right, but his near-post cross is headed away from danger, although Arsenal win a corner.

Costa tries an ambitious effort from 30 yards out on the right and wins a corner for a touch off the covering defender.

Bacary Sagna gets away down the right, but no-one is in the middle to meet his deep cross.

Fabregas is dictating play in midfield at the moment, Porto need to close him down and deny him the time and space to pick his passes.

Exactly what was needed for the home side and Wenger looks relieved as much as anything on the bench.

Half an hour played and the danger signs are out for Arsenal, they have to turn good play into goals more often.

The Gunners almost fell behind there, they fell asleep from the set-piece and almost paid the penalty.

From the corner Lopez almost breaks the deadlock again as he pounces from close range, but his effort is blocked on the goal-line by Gael Clichy.

Lisandro Lopez almost rocks Arsenal, finding space 25 yards out and rifling in an effort which is turned behind for a corner by Manuel Almunia.

Rodriguez plays a long ball over the top to the right, but Gallas is across superbly to mop up the danger.

Midway through the first half and the home side look the more likely to find a goal at the moment.

Fabregas and Walcott combine again on the right, but an offside flag ends any hopes of a breakthrough.

Arsenal are playing most of the football, but yet again need to find an end product.

Fabregas is again at the hub of things, flicking a ball in to Walcott on the right and he wins a corner.

Fabregas lifts a fine pass in towards van Persie, whose right-foot shot goes into the turf and drops onto the roof of the net with Helton having it covered.

Good chances at either end now, the game has picked up pace again.

Porto almost catch Arsenal cold at the other end as Cristian Rodriguez meets a right-wing cross from Tomas Costa and his downward header goes over after clipping the top of the crossbar.

Another quality attack see Cesc Fabregas find Robin van Persie 25 yards out and he extends Helton with an accurate low, left-foot drive.

Walcott tricks his way past a couple of defenders, but is eventually crowded out as he drifts inside off the right flank.

The Gunners burst into life and a fluent attack ends with Theo Walcott forcing Helton into a smart save at his near post.

The play has become a bit edgy now, Arsenal's early promise has slowed a little.

Freddy Guarin threatens to take advantage of a defensive slip, but slips himself and his pass inside in cleared away by William Gallas.

Play has been all in the Porto half so far, Arsenal certainly look fired up.

A bright start from the Gunners as Nasri leads a quick attack which eventually ends on the edge of the Porto penalty area.