Jamie Roberts
Wales international centre on BBC Radio 5 Live

I am not sure what to say about the Irish performance. The discipline has been atrocious. Wales have one hand on the Grand Slam.

Image source, AFP

Tick-tock, drip-drip. Wales are inflicting death by a thousand cuts. Another three points onto the pile and Ireland are almost buried underneath.

Dafydd Pritchard
BBC Sport Wales at the Principality Stadium

There's a little apprehension in the air at the start of this second half.

Wales' supporters could hardly have wished for a better first 40 minutes but, in an inherently Welsh kind of way, there are a few whispers among the fans near the press box that they're still nervous. Things are almost going too well.

Conor McNamara
BBC Radio 5 live commentator

Ireland are in shambolic state here.

Ireland's scrum is under pressure once again. Conor Murray does well to get it away from a retreating set-piece.

But Cian Healy is pinged for taking out Tomas Francis who was only connected to the maul by his fingertips.

That looked marginal.

Gareth Anscombe doesn't care. He is lining one up from central and 30m out.

Wales are looking for what would surely be the knockout blow. A rumbling rolling maul is heading towards the Ireland 22m...

But superb play from Cian Healy, who drives a wedge between the red shirts, gets his mitts on the ball and keeps it off the floor as the whole thing heads south.

Green scrum, 30m from their own line.

Joel Hughes: For a Welsh person, the next 40 mins will take approx 5 years off your life.…

John McEnerney: Beating the All Blacks is a distant memory now for us as I said then you don’t win the 6Ns in November. Wales showing us up big time & we deserve the hiding they’re giving us. Fully focused is what Wales are & clinical like Ireland in 2018 but it’s 2019.

Nic on Edinburgh: Ireland are playing like they know they'll give the 6 Nations to England if they win!

Garin Jenkins
Former Wales hooker on BBC Radio Wales

There was a lot of talk before the game about the roof being open - Wales are the ones who have adapted to it.

Reminder: Ireland asked for the roof to be open when rain was forecast

By the way, the rain that all the forecasts said was in the post? It has arrived.

An absolute deluge thumping out of the Cardiff sky.

This is not the weather to chase a game. And right on cue, Johnny Sexton chops a kick out on the full from just inside his own half...

Image source, Reuters

Simon Gleave
Head of sports analysis, Gracenote

Ireland haven't been this far behind at the break of any Test for nearly seven years - since going in 29-0 down against New Zealand in Hamilton in 2012. Ireland lost 60-0 that day.

Ireland get a taste of their own choke-tackle medicine.

Conor Murray looks on exasperated as Alun Wyn Jones keeps James Ryan off the deck to secure a turnover.

A cliff-hanger or a cornation?

It is looking like the latter at the moment.

We are up and running in the second half.

Chris Jones
BBC rugby union correspondent at Twickenham

Wales aren't losing this game on that first 40 minutes. Come 5pm Twickenham won't feel as lively as it might have done.

Eddie Jones is really keen that his team prepare exactly the same way as they normally would. He would hate it if his side attempt to play champagne rugby. He will want a ruthless controlled performance no matter what happens in Cardiff.

Chris Henry
Former Ireland flanker on BBC Radio Ulster

Wales are winning the 50-50's and just showing better quality at the moment.

Ireland need to get back to basics and concentrate on their ball focus but if they can't turn things around then Schmidt will need to think about using his bench earlier than usual. If Wales get another score early on, then maybe somebody else needs to get a chance.

Johnny Sexton and Conor Murray are used to playing with dominant forwards at their provinces but Ireland are not getting off the gainline and off course that makes it difficult. You can see their frustration out there.

Peter Stringer
Former Ireland scrum-half on BBC One

Ireland have got to get the first score in the second half. They've got to get down in the opposition 22 and retain that ball. It's about getting in the right areas and chipping away. They've got to clear that slate.

Dafydd Pritchard
BBC Sport Wales at the Principality Stadium

Those who like a neat narrative might be interested to note that Wales trailed France 16-0 in their opening match of this Six Nations.

They turned that game around in spectacular fashion and now they stand on the verge of a Grand Slam with a half-time lead over Ireland of... 16-0.

Ian McKeown: When are the Ireland team showing up at the match.

Small Man Peaky: Ireland are mentally shot. The England game exposed their limitations. Against a Wales team with this level of confidence they are crumbling. Sexton completely lost his head. Wales deserved GS if they go on and win this.

strokebet: Wales have continued what they have been good at all 6 nations. Unbelievably solid in defence, good decision making in attack. And they have had a bit of luck. Parkes has been absolutely superb. They couldn’t have hoped for a better first half.

A quick half-time selfie for the 5 Live commentary team.

You'd think Jamie Roberts would look a bit happier...

Image source, BBC Sport

Image source, Getty Images

It has been a team effort from Wales rather than any flashes of individual brilliance.

It is kind of summed up by their captain.

Alun Wyn Jones is the hosts' leading metre-maker (with just 12!), ball-carrier (five carries) and defender-beater (two).

Champagne rugby from a man who looks like he prefers a pint of mild.