Ireland attempt to turn the screw on an underpowered Wales pack, but Wayne Barnes has spotted Jack McGrath's sly sideways step to bring on the wheel.

A much needed penalty for Wales to ease the pressure and eat up the seconds.

Jamie Roberts has come in out of the centres to make up the numbers in the scrum, packing down on the blind-side.

You would think twice before picking and going down the short side with him there.

Phillip Matthews
Former Ireland captain on BBC One

Image source, PA

"Ireland are going to have to make the most of this yellow card. Warburton has been prolific in his line-out and defensive work so far. He got the word from Wayne Barnes to roll away... and he didn't."

Jonathan Davies
Former Wales fly-half on BBC One

Image source, PA

"You have to listen to the referee. Even if you feel you are supporting yourself, you have to listen to the referee and if he says 'roll away', you roll away. Wayne Barnes has been consistent and that is all you can ask for."

That radar is back in working order. Johnny Sexton makes his kick and a 12-point lead has been cut in half with a 10-minute "power play" to come for Ireland.

Image source, PA

"You've had your warning Sam."

Wayne Barnes dispatches Sam Warburton to the sin bin as he gets his hands all over the ball right in front of the official.

Not Warburton's smartest work.

Johnny Sexton will have a chance from straight in front and on the Wales' 10m.

Image source, Getty Images

John McEnerney on Twitter:, external "Wales playing outstanding stuff. Crucial 15 mins for Ireland."

Steve Jones on Twitter:, external "Leigh Halfpenny is a superb example for kids of what you can achieve with commitment."

Wales are burgling the Ireland line-out.

Dan Lydiate gets up to claim another of Rory Best's darts before Liam Williams shows that you don't need a childhood playing Gaelic football to claim a box kick, clambering highest to regain Rhys Webb's steepling punt.

Phillip Matthews
Former Ireland captain on BBC One

"The way Wayne Barnes is refereeing this, he is favouring the side with the ball. With the way it is going, you would therefore favour Wales to win it."

Jonathan Davies
Former Wales fly-half on BBC One

"They read the call, the lifters knew it was coming, so they could get Sam Warburton in the air to steal the line-out and then Ireland gifted them the present of a penalty by taking him down in the air."

Huge cheers! Sam Warburton squirts up at the back of the lineout to steal a ball aimed for Devin Toner.

Ireland give away a penalty - taking out Warburton in the air - to compound hooker Rory Best's error and pave the route out of defence for Wales.

Three penalty advantages and Johnny Sexton kicks the last into the corner to give Ireland a lineout thrown five metres from the Wales line...

BBC Wales Sport's Dafydd Pritchard at the Millennium Stadium

After a breathless start, the Millennium Stadium fell silent for a moment as Wales prop Samson Lee was taken off injured.

Until then, it had felt like a firework display here - only that it has been brutal tackles rather than pyrotechnics creating the spectacle.

Each ferocious hit has been met with cries of "ooh" and "aah" as Welsh and Irish players crash into each other like dodgems on the pitch. This is not for the faint-hearted.

BBC Sport's Ben Dirs on Twitter:, external "I'm not sure anyone expected this, Ireland just haven't fathomed Wales' variety of attack. They've slept walked into a threshing machine."

Wales have the ball back in hand but Alun Wyn Jones bites off more than he can chew, charging into the entire Ireland back row.

Jamie Heaslip and Sean O'Brien gobble him up, freezing his forward momentum and keeping him hanging off the floor to earn the turnover.

Image source, Getty Images

That is more like normal service.

Johnny Sexton finds the sweet spot of the instep, hammering clean off the tee to split the sticks.

Another chance for Johnny Sexton. Scott Baldwin to blame for Wales with a needless high tackle near halfway.

Ireland have been on the rough side of Wayne Barnes' whistle so far, but they have a break there with George North pinged for hanging on to his man after the tackle.

It is a tricky chance, off on the angle, but Johnny Sexton won't be happy with the tugged effort.

He has had a slow start .

Jonathan Davies
Former Wales fly-half on BBC One

Image source, Reuters

"This will not be good for Wales, Samson Lee is crucial to the scrum. It is a big ask for his replacement Aaron Jarvis and it also ends the momentum Wales had built up. This is a big blow for Wales, a big blow. And a certain Adam Jones has retired. Adam, put your pint down and get back on the treadmill..."

Martin Aaron on Twitter:, external "What a start for Wales! Let's hope we can keep this going."

Dave Harrington on Twitter:, external "Where is this well disciplined Irish side everyone's raving about?"

Matt Cross on Twitter:, external "Convincing start so far, Ireland not having enough ball to show how dangerous they are."