Welcome to our LIVE coverage of this opening match of the Six Nations.

Leigh Halfpenny will take the shot at goal - and makes no mistake, slotting it straight through. Ireland's lead cut to 20-3.

Conor Murray tries to run the ball out of his own 22m after that throw - a terrible decision as he is ultimately penalised for hanging on in the tackle. It's a penalty dead in front, just outside the 22m. Surely Wales must kick to chip away at the deficit?

The Welsh keep patient for several phases moving back and forth across the 22m, and they're finally pushed out on the right-hand side: throw-in to Ireland and a chance to clear the decks.

A chance for Wales to get back into it before the end of the half: they win a penalty from the restart and kick for touch in the 22m, then keep the line-out tidily...

Time to start looking through the record books for Wales's worst defeat in Cardiff...

Sexton takes his time lining this tough chance up, but it's worth the wait: a perfect strike sends it clean through despite the acute angle. 20-0!

From bad to worse: Mike Phillips drifts offside trying to get ahead at the line-out, and Sexton will have a chance at goal from just outside the 22m and on the left touch-line.

It's all going Ireland's way: Wales push forward from the restart, but Faletau is tuned over and Connor Murray's cheeky clearance bounces miles upfield and into touch at the Welsh 22m.

Unbelievable scenes in Cardiff as Sexton nails the conversion to make it 17-0 - the Welsh are all over the place.

Ireland score another try! Incredible stuff from the visitors, with Rory Best starting it off with a charge-down of Biggar's clearance - he doesn't make it to the line, but delivers it out to Heaslip, who passes to Zebo, who performs an incredible back-flick with his heel to keep the ball under control! Two more phases follow and Ireland's Healy goes over for a try!

Brian O'Driscoll is getting some tape for a bloody forehead now - Matt Rees is back on, apparently with five stitches in his noggin!

Sexton brings it back just inside the 22m to improve the angle, and bangs it through - 10-0 is Ireland's lead, and the Welsh are reeling right now.

Heaslip decides not to go for the line but instead to turn this pressure into points - Sexton faces a shot at goal from all of 12m, and slightly to the right. Unmissable.

There's a Wales knock-on as they try to clear the ball, and Ireland have a scrum right in front - four phases bring them no nearer the try line, and as the ref signals a penalty Sexton tries a free shot at a drop goal that narrowly misses.

Replays suggest that Gilroy's attempts to sidestep Halfpenny were a bit pointless and that he should just have piled straight through. Ireland looking lethal right now, however.

Ireland's pack try to build through the centre for several phases, but it's finally spun out to O'Driscoll, who almost puts Gilroy in at the corner. He's held up just two feet short!

Ireland really turning the screw now: Sexton slots a great ball though to put Leigh Halfpenny under pressure, and he slices the ball out for an Ireland throw on the Wales 22m.

Sexton kicks for touch from that penalty but then his colleagues up front mess up, with Peter O'Mahony spilling the ball towards the red shirts. Terrible waste of a good platform, but they get another chance as its spun wide to Cuthbert, who misses the ball and lets it off the other side of the pitch.

Ireland win another penalty for Wales collapsing the scrum, Adam Jones the man at fault this time.

Another blood delay, with that cut on Matt Rees's face needing more staples from the docs. Ken Owens has come on while he's patched up.

Dream start for Ireland - Zebo is earning just his fourth cap today, but finished that one off like a nerveless veteran.