Michael Hector is involved a lot again in the Reading defence. A massive up and under to clear is quickly followed by a trip on Alexis Sanchez. He just could not live with a clever touch.

A crossing chance for Santi Cazorla and Per Mertesacker senses another Wembley goal but he diverts the ball wide off his back. He threw his head at it but judged the flight of the ball wrong.

Here we go again. A huge section of seats on halfway are empty as the teams get things going again. The shade has moved so Arsenal's defenders will again be under it. And Reading win an early free-kick in the oppositions' half.

Kurt Booth: Sanchez demonstrated in that finish the kind of dead-eyed calm he has brought to Arsenal which has helped settle a nervous team.

Rishi Verma: A shame Reading aren't able to make more use of the ball in the final third of the pitch after working so hard to retrieve it.

Jordan Cole: How average have arsenal looked but give a player like Sanchez half a chance and he'll take it.

Patrick Coppins: That is what a combined £75million gets you. Pure class from Ozil and Sanchez.

Former Arsenal & Reading defender Martin Keown
BBC Radio 5 live at Wembley

"Reading have been very brave, they've played a very high line. Arsenal interchange brilliantly and as soon as they get in behind your midfield, you're vulnerable. Steve Clarke's side started very well, I thought Jamie Mackie was really unlucky to have been given offside. They just need a little bit more care and belief. The manager will be in there now trying to inspire his players, because these opportunities don't come around very often."

Former Reading striker Jason Roberts
Match of the Day at Wembley

"I was hoping Reading would begin in the way they did. They were compact and organised and pressured Arsenal. But you can't do that without leaving space in behind. For 39 minutes they performed so well but Mesut Ozil, with a little bit of quality, has undone them. There will be chances for Reading though."

Image source, Opta

Ozil has been busy picking the ball up all over the final third as he drifts around. His 58 touches is only bettered by Santi Cazorla's 62.

Former England captain Alan Shearer
Match of the Day at Wembley

"In fairness to Reading I thought they were brave to play two up front. Not a lot of teams do that against Arsenal and they got tight on them. Steve Clarke's side acquitted themselves well but that one bit of quality for the goal was top drawer. On the whole though Arsenal will be disappointed in the way they have played. For 39 minutes they were poor. Lethargic and sluggish."

Image source, Opta

Arsenal have had 74% of the ball but much of the play has been in midfield with Reading working hard to cut out balls into the final third. The Gunners made just six tackles in the first half.

Former England midfielder Danny Murphy, BBC One
5 live Sport

"They have done well Reading, they have to be careful to not feel sorry for themselves and take the positives out of the half. They have not been in lots of trouble, they have been defending for their lives courageously. They will get a chance in the second-half."

Image source, AFP

Nabil Hassan
BBC Sport at Wembley

"That goal was tough on Reading but it had been coming with Arsenal continually knocking on the blue door. It needed a magical pass to unlock that Reading defence and now at half time it is the Arsenal fans who can sense yet another FA Cup final. Reading have 45 minutes to find a way back into this game."

Image source, AFP

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Alexis Sanchez had 35 touches in that opening period and ultimately had the most important one. He completed 79% of his passes. Mesut Ozil is on 94%.

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Former England winger Chris Waddle
Match of the Day live at Wembley

Steve Clarke needs to get his team sorted out because their concentration is dropping. Has Clarke got a plan B? If he doesn't you can really see Arsenal running away with this."

Image source, Getty Images

Those are the margins I guess. A half full of fight and on times rush defending by Reading ends with a brief lapse in concentration, a well-timed run and potentially a decisive moment.

What now? Does Steve Clarke call for more attacking intent and risk watching the horror of his side being picked off?

As the half draws to a close Nathaniel Chalobah blots his copy book with a tackle on Kieran Gibbs. It's a bruiser, not dirty, but enough for a yellow.

Former England midfielder Danny Murphy, BBC One

"You can't keep good players quiet. Sanchez has been frustrated up until now but what a great finish that is, how calm he was. It was the first opportunity in front of goal. There was a patient build-up, with a packed defence and a brilliant pass from Ozil. That's the quality you get. Sanchez was a little bit fortunate, the shot just popped through the keeper's legs."

Danny Williams is at the sharp end of the break in the Arsenal penalty area but he cannot volley a dropping ball on target, it dribbles well wide of goal.

Danny Welbeck - a man Arsene Wenger admitted he was surprised by when he saw how quick he was in training - is using his leggy stride to bounce through the Reading defence but his cut-back his hacked for a corner. A second corner follows but now Reading break...

That's 21 goals for the season for Alexis. His reward? A naughty little foul by Danny Williams who leaves a little bit on his man when the ball has gone.

Former England winger Chris Waddle
Match of the Day live at Wembley

"A class goal from a class player. It was a lovely ball in from Mesut Ozil, and Alexis Sanchez provides a quality finish. His movement and his touch is so good. Reading just have to keep it tight until half-time now."

Alexis Sanchez makes the sign of the cross, he has a goal at Wembley and it oozes quality.

Quality in the build-up as Mesut Ozil shapes onto his left foot 40 yards out and curls a ball over the centre of the Reading defence to find the run. It's there to bang but Sanchez resists and wrong foots the covering defender. A pause, a prod of his right foot, it's under Adam Federici from around 10 yards and that is a big, big goal at a great time for Arsenal.

Nabil Hassan
BBC Sport at Wembley

"Steve Clarke will be relatively pleased with Reading's start. They're compact and organised and Jamie Mackie is providing his side with a threat up front. Clarke spent much of the opening 20 minutes patrolling his technical area barking instructions as things quieten down at Wembley."