Phil McNulty
BBC Sport chief football writer at Emirates

Image source, Getty Images

Wide open at The Emirates - moments of anxiety for Arsenal while opportunities on the break for Alex Oxlade-Chamberlain and Theo Walcott at the other end. Olympiakos coach Marco Silva was so peturbed by one Arsenal counter that he indulged in a spectacular Basil Fawlty-style dance of fury in his technical area.

BATE Borisov of Belarus (that's Borisov Automobile and Tractor Electronics for you and me) have taken a surprise lead at home to Roma - they're 2-0 up already!   

In the other game in Chelsea's group, Dynamo Kiev have taken an early lead at Maccabi Tel Aviv, while in the other game in Arsenal's group, Douglas Costa has scored to put Bayern Munich 1-0 up at home to Dinamo Zagreb.

Image source, Reuters

What a pass! What a touch! Pedro's first touch is wonderful to tame a ball pinged into him, he can't quite get the ball out of his feet though and Iker Casillas is able to make the save with his feet.

Saint Iker indeed! Jose Mourinho is not happy, the Dragao is booming. Great noise. 

The game has come alive. Brown Ideye is close to steering in a free-kick from the right for Olympiakos but again Arsenal counter like a cornered snake, freeing Theo Walcott on the burst but his shot is poor. 

Mark Lawrenson
BBC Radio 5 live in the Estadio do Dragao

"It's a really lively game here, it's been a good start. Diego Costa is looking very, very sharp.

"Chelsea know they're going to be in a game but they also know they can cause problems on the counter attack. Porto do commit players forward." 

Tom Haydon: Re:19:43. Atletico Madrid might be in with a shout there!

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Olympiakos obviously didn't watch MOTD on Saturday as they are caught on the break just like Leicester were time and time again.

The Greek side have a corner, Hector Bellerin heads it out and Arsenal are go-go-go!

Alexis Sanchez frees Alex Oxlade-Chamberlain sprinting into the box, he shoots near post - side netting. Should go across the keeper!

Alexis Sanchez cuts in from the left and wants a free-kick as he takes a tumble but referee Bas Nijhuis says no. Olympiakos then counter for the first real time and former West Brom man Brown Ideye is close to reaching a ball over the top. 

Diego Costa down the left-hand channel, holds it up well, needs support - and has it. He pulls the ball back to Cesc Fabregas 20 yards out, foot through it but Iker Casillas watches it like a hawk and turns it away. Good game so far.

Alex Oxlade-Chamberlain gives it some gas down the right wing but Dimitris Siovas does well to track him and make the challenge. Arsenal look comfortable. 

If your CV had a section for those life skills that you rule at - no matter now trivial - what would you have to offer?  

Start your message with :"I am UNTOUCHABLE at..."

Tom, Clapham: I am UNTOUCHABLE at reciting the alphabet backwards at full speed while belly dancing. Let me know if you want the video.  

Get in touch at #bbcfootball,, external pop on to the Match of the Day Facebook page, external or BBC Sport's Google+ area. 

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Well, yes. Obviously. 

Don't forget you can listen to full match commentary from Porto using the Live Coverage tab at the top of this page.

A rare start for Jon Mikel Obi in the Chelsea midfield tonight. He's a season away from a testimonial at the club - extraordinary. Who thought he'd still be around?Must be 'terrific in the dressing room.'

Mark Lawrenson
BBC Radio 5 live in the Estadio do Dragao

"We thought Willian was playing through the middle, but he's on the left. Cesc Fabregas is playing nearer to Diego Costa, and Pedro is on the right. 

"I presume this Chelsea XI hasn't ever started together before, so they'll need 20 minutes of consolidation I would have thought."

Lovely feet from Yacine Brahimi as he turns away from two Chelsea players in midfield and gets a shot off from 22 yards - straight at Asmir Begovic though. Pedro did well to get back and hassle him.

Porto starting well as Andre Andre almost gets in behind Gary Cahill. 

Plenty of empty seats at Arsenal. Is this one you'd give a miss?

Image source, Getty Images

Under way across the Champions League...

Struggling Crawley will be hoping to stop a four-game losing streak against Newport, who are one place below them in last place.

Unbeaten Portsmouth will equal their best league start in 15 years if they avoid defeat to Exeter who are winless in their last three.