Jermaine Jenas
Former England midfielder on BBC Radio 5 live

You can't allow Pedro that space on the edge of the box. 

In fairness he works it well and lets the ball come across his body. When he does that the picture changes.

He will look at that as a missed opportunity. He should have done better.

It can only be a matter of time before Chelsea open the scoring. Pedro collects the ball from the right, transfers it to his left foot and bends a shot past Ben Foster - but wide!

Sam Field is the latest Albion man into the book as he lunges in and takes out Pedro in full flight. Still 10 minutes to go until half time. 

Image source, Rex Features

Jermaine Jenas
Former England midfielder on BBC Radio 5 live

McClean has got to start defending.

He keeps throwing himself at Moses and diving in. 

He is very fortunate, he can't keep putting in challenges like that.

Image source, PA

James McClean is having a torrid time with Victor Moses. He can't tackle, in fact.

Already booked, he lunges in again and takes the former Palace and Stoke man out.

'One more and he's #*#*@*/*/~@@~ off!' is the correct shout from Tony Pulis on the sidelines.

Cesc Fabregas then shoots just wide from 20 yards. 

Phil McNulty
BBC Sport chief football writer at The Hawthorns

Chelsea have had some very slick approach work but have been let down by sloppiness in the final third - and their corners have been awful so far.

Cue Chelsea goal from a corner...

Image source, Reuters

This is the fifth occasion that Chelsea have attempted 10+ shots in the first half of a Premier League game this season. They scored in the other four games.

They have 15 more minutes to go too. 

Jose Holebas looks like he's having fun on that left flank for Watford, if these attacking stats are anything to go by...

Image source, .

I think Eden Hazard is the player I'd least like to track in a game of 5-a-side. Always moving. He drifts from left wing to right wing to penalty area in the space of about five seconds. Leaving three defenders in his wake as he does so. 

Everton youngster Tom Davies has a spark in him, he's furious when pulled by Valon Behrami and there's a mini scuffle as a result. Two men are booked in the aftermath. 

Image source, Reuters

A great question Tom, and not one that I know the answer too. Somebody may be able to help.

Eden Hazard plays a one-two with Pedro, dances in to the area and is bundled over by Jonny Evans - no penalty though, and no real appeals either. 

Tom Gill

Image source, Getty Images

Watford are a man down as Christian Kabasele limps off - on in his place comes Juan Zuniga.

Image source, Getty Images

Some brilliant defending from West Brom. James McClean is booked for a not too clever tackle on Victor Moses and the resulting free-kick comes through to Gary Cahill.

The England man smashes in a shot - Gareth McAuley appears from nowhere to block with his abdomen. Superb from the 37-year-old. 

Image source, Reuters

Chelsea are dominating the possession stats in the first 20 minutes. West Brom have had only one touch in the Blues' box so far, and that came from Rondon after 23 seconds. 

Image source, .

Chelsea look a cut above so far tonight but West Brom do pack a punch on the counter. Salomon Rondon is giving game chase to every long ball punted in his direction, and he nearly gets away from David Luiz and into fresh air but the Brazilian just about clears his lines. 

Image source, Getty Images

Jermaine Jenas
Former England midfielder on BBC Radio 5 live

This is a lot of pressure that Chelsea are putting on West Brom now.

Cesc Fabregas, cooking on gas tonight, slides a free-kick short to Pedro, whose shot is deflected narrowly wide.

Another short set-piece ends with Cesar Azpilicueta shooting over via a deflection. The pressure is growing and growing...