Work to do for Villarreal, they were well off the pace in the first half.

Away we go again.

Jared Maobe: Where exactly is Odoi's strength? To me, he hasn't grabbed anything really attack wise, and defending, it's his least thing really.

Paul C: Chelsea will be expected to challenge for the title this season. If they don't then Tuchel will be sacked. Especially after spending nearly £100 million on Lukaku. He sacked Di Matteo not long after winning the Champions League so that's no guarantee of safety if they don't go close to the title.

Lewis Starks: Rudiger has made what every fan wants to see and that is a tackle. Never a foul and then 2 people booked for an incorrect decision. Compounded

Mark Sterling
BBC Sport NI at Windsor Park

Thomas Tuchel looked like he was having a pretty pleasant and relaxed evening in Belfast until a few minutes before half-time.

The Chelsea boss stood calmly, hands in pockets, on the edge of his technical error for most of the opening half but his demeanour changed when goalscorer Hakim Ziyech went off with what looked like a worrying shoulder injury.

Tuchel looked agitated as he took to his seat in the dug-out for the first time in the evening and he was ruffled again a few minutes later when he was shown a yellow card for his complaints about Kurt Zouma getting booked for a heavy challenge on Yeremi Pino.

Alberto Moreno then crashed a volley against the crossbar as what had been a commanding stroll of a first half in Belfast for Chelsea ended in somewhat chaotic fashion.

Image source, Getty Images

Stephen Warnock
Former England defender on BBC Radio 5 Live

It's always a dangerous score 1-0 - especially when you're so dominant in the game - but it can only take one lapse of concentration as we've just seen there to change it all.

It could have been a completely different story if Moreno had buried that.

Chelsea were in total control but survive that chance late in the half for Villarreal.

A bittersweet half for Hakim Ziyech, scoring the only goal before going off injured with a painful-looking shoulder injury.

Image source, Getty

Image source, Getty Images

What a hit from Alberto Moreno, picked out at the far post and smashing a thunderous volley against the crossbar from five yards out.

It bounces on the line and away from goal, no way did it cross.

Looking back at the replay, Moreno should score, how has he not from that close in??

Stephen Warnock
Former England defender on BBC Radio 5 Live

Very poor from Manu Trigueros - absolutely rubbish that ball was.

From the free-kick, Manu Trigueros' poor free-kick is cleared by the first man.

That was awful.

Now Chelsea boss Thomas Tuchel is booked, presumably for something he has said to the fourth official.

Sergei Karasev getting a little card giddy here.

Arjun Singh: Gutted for Ziyech. His season last year started the same way - with injury - and he’s been on fire in this year’s pre-season as well. Hope it’s not as bad as it looks

Oh my, Yeremi Pino will feel like he has been hit by a car as Antonio Rudiger comes across and completely takes out the Villarreal forward after getting the ball.

A hefty challenge from the German and he receives a booking for the follow through.

Rudiger isn't happy with that, nor are some of his Chelsea team-mates.

Hakim Ziyech uses his blue Chelsea shirt as a sling and hobbles off in a lot of pain. It's etched all over his face.

The goalscorer is replaced by American Christian Pulisic.

Image source, Reuters

Stephen Warnock
Former England defender on BBC Radio 5 Live

This doesn't look good.

He's lying on his back, with an inhaler by the looks of it.

He looks okay, he doesn't look like he's in any great distress but they're being very cautious with him.

It's a lengthy stoppage as half-time approaches.

Christian Pulisic is getting some instructions, Hakim Ziyech's race looks run here.

Ziyech is using some sort of inhaler device while on the ground and continues to hold his shoulder as he sits up.

Chelsea goalscorer Hakim Ziyech is down on the deck and looks in a bit of trouble, grabbing his right shoulder.

It looks an innocuous one with Juan Foyth in close attendance.

Mateo Kovacic breaking through the heart of the Villarreal midfield and is shoved over.

The Croatian grabs the ball as the referee blows the whistle for a free-kick...awarded to the La Liga side for handball.

Stephen Warnock
Former England defender on BBC Radio 5 Live

What a phenomenal ball - an absolute peach of a ball.

The quality of ball is simply sensational - it could easily be more than 1-0 here.

Image source, Getty

Should be two, how did he miss??

Goalscorer Hakim Ziyech curls in a delicious deliver to the edge of the six yard box, centre-back Kurt Zouma stretches out a leg and somehow volleys it over the crossbar.

The chances are coming for Chelsea, they can put this one to bed before half-time if they keep pushing.

Left wing-back Marcos Alonso makes his way into the Villarreal box and a low, carefully placed shot is palm away by the diving Sergio Asenjo.

Image source, Getty

Mark Sterling
BBC Sport NI at Windsor Park

Northern Ireland has been waiting a long time to host a club match of this scale on the European stage.

And if the noise inside Windsor Park is anything to go by, the wait has been worth it.

It may be a curtain raiser for the season, but this very much has the feel of a proper match played out in a fantastic atmosphere contributed to by two large, vocal sections of supporters.

The sun may have just gone down in south Belfast, but the temperature inside the ground certainly has not.

You love to see it.

Image source, Reuters