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A Bayern Munich fan shows support for their team. Mike Egerton Mike Egerton

A general view of the Allianz Arena. Mike Egerton Mike Egerton

We’re underway…

It’s been a very scrappy start.

Both sides are giving the ball away cheaply and not much of note has happened yet.

Still not much in the way of goalmouth action thus far.

Bayern have had the far better possession and territory, but the visitors have held firm.

As I type, Vidal’s shot from the edge of the area is comfortably saved by Ospina.

BAYERN 1-0 ARSENAL (ROBBEN 11)

Out of nothing, Robben gives Bayern the lead with a beautiful curling strike from the edge of the area that finds the top corner.

Coquelin will be disappointed, as he stood off the Dutch attacker and allowed him the space to score in spectacular fashion.

Lewandowski threatens to run through on goal but Koscielny makes an excellent tackle to stop him.

Suddenly, Arsenal are on the ropes.

Here’s a look at that superb Robben goal.

The goal has not really had any impact on the pattern of play.

Bayern are still in control of the game and look like scoring a second.

Arsenal manager Arsene Wenger. Mike Egerton Mike Egerton

Sanchez gets a rare chance to counter, but he’s outnumbered and Hummels easily steals possession from him.

Arsenal have offered minimal threat so far.

PENALTY TO ARSENAL!

BAYERN 1-1 ARSENAL (SANCHEZ 30)

A poor penalty by Sanchez is saved by Neuer, but the Chilean international does well to keep his composure, taking a touch before blasting home the rebound.

Arsenal scarcely deserve it, but they’re back in this game.

Shouts for a penalty as the ball hits off Bellerin’s hand in the Arsenal.

The referee ignores claims and the home crowd are not happy.

Bayern are still not happy about the Arsenal penalty but it looked pretty clear cut.

Lewndowski failed to make contact with the bouncing ball and booted Koscielny in the process.

Oxlade Chamberlain crosses for Xhaka, whose shot on the edge of the box is powerful but straight at Neuer.

Arsenal have looked a lot more confident and purposeful since the equaliser, with Sanchez leading by example with his hard running and touches of class.

Alaba crosses for Lewandowski, but the Poland international can’t keep his header down.

For all their recent positive play, Arsenal still do not look secure at the back by any means.

Hummels heads an inswinging free kick just wide amid more shoddy marking from Arsenal’s defenders.

This game certainly has more goals in it.

HALF-TIME: BAYERN 1-1 ARSENAL

So half-time, and it’s been a fascinating game.

Bayern took the lead through a brilliant Robben strike, and looked in total control, until Lewandowski needlessly conceded a penalty with a careless challenge on Koscielny.

Since then, Arsenal’s confidence has been renewed, though with both sides’ defences looking vulnerable, it’s hard to predict which way this game is going to go.

Here’s a look at Sanchez eventually scoring after missing the penalty.

The second half has begun…

Blow for Arsenal early in this second half.

Koscielny hobbles off injured and is replaced by Gabriel.

BAYERN 2-1 ARSENAL (LEWANDOWSKI 54)

It’s a vintage Bayern goal that restores their advantage.

The hosts counter and Lahm’s cross is beautifully headed home by Lewandowski, who towers above his marker while scoring.

BAYERN 3-1 ARSENAL (THIAGO 57)

Bayern score two in two minutes as Arsenal capitulate.

It’s a lovely backheel by Lewandowski to play through Thiago, who finishes consummately.

The hosts were given far too much space to play there — Arsenal have been poor at the back all night.

So close! Lewandowski rounds the goalkeeper and hits the crossbar from a tight angle.

Robben’s follow up is then deflected just wide.

BAYERN 4-1 ARSENAL (THIAGO 63)

Arsenal fail to properly clear a corner and Thiago’s shot deflects in off Xhaka.

Three goals in 10 minutes mean Bayern now have one foot in the next round — Arsenal desperately need a goal to keep themselves in this tie.

In reaction to that goal, Arsenal make an attacking change.

Walcott replaces Iwobi.

Here’s a look at the three goals that have put Arsenal firmly in control of this tie.

Arsenal look a beaten team now.

Bayern are controlling the game, and the way the Gunners are defending, it would be no surprise to see them add to their tally in the final 20 minutes.

Claims for a penalty as Lewandowski goes down under a risky challenge from an Arsenal defender.

It’s unlikely to matter in the long run though — the Gunners look increasingly devoid of energy and enthusiasm.

Another very attacking change for Arsenal, as Giroud replaces Coquelin.

Arsene Wenger’s side certainly won’t die wondering.

Gabriel nudges Lewandowski over in the box as they both run for the ball, but the ref again waves play on.

Bayern have had at least four penalty shouts at this stage, and Arsenal, in truth, are probably lucky to be only 4-1 down.

The visitors have completely crumbled in this second half.

Ospina tips away a powerful Costa shot from just inside the box.

Despite conceding four, the goalkeeper has played well tonight. Arsenal in general, by contrast, have offered so little in this second half.

As I type, Costa is replaced by Joshua Kimmich.

Walcott bursts down the right, but Martinez does well to stop the cross from reaching Giroud.

Down the other end, Robben plays through Kimmich, but his shot from a tight angle is well off target.

Thomas Muller gets a chance to impress in the last few minutes, as he takes the place of Lewandowski, who has been brilliant tonight. In addition, Rafinha also comes on for Robben, who scored that exceptional opening goal.

BAYERN 5-1 ARSENAL (MULLER 88)

Oxlade Chamberlain concedes possession on the edge of the box.

Thiago then plays it to the substitute Muller, who finishes calmly.

Here’s a look at Muller’s composed finish, after another dreadful Arsenal error.

There’s no doubt that the loss of Koscielny has had a big impact.

Arsenal have been so porous in defence, particularly in this second half.

5-1 is in no way flattering to Bayern, given how superior they have been in the second half.

FULL-TIME: BAYERN MUNICH 5-1 ARSENAL

Right, that’s all from me on a bad, bad night for Arsenal.

Thanks for reading and commenting, and we’ll have more reaction to follow.