Hello and welcome to ESPNscrum's live coverage of the second game of this year's Six Nations championship - defending champions Ireland visit Italy in Rome, looking to avenge a shock defeat when they last visited this city in 2013.

We have dramatic breaking news: Sean O'Brien is OUT after getting injured in the warm-up. Tommy O'Donnell starts at No.7, Robbie Diack is added to the Ireland bench.

First up is the Irish anthem, and it's getting a rousing - if slightly uncoordinated - belting from the travelling fans. The Italian band appears to be playing it deliberately slowly...

No such syncopation problems for the Italian anthem, which is rattling along at its appropriately jaunty rate.

And from that scrum, a penalty for Ireland, as Matias Aguero fails to bind.

Some problems setting the scrum - the Stadio Olimpico pitch is tearing up terribly under the pressure of the packs hunkering down. That's going to be an issue, especially due to pre-match rain in Rome.

Terrific robbery from Conor Murray as Italy fail to deal with a garryowen. Italy eventually clear their lines but they are under the cosh, especially up front.

Not much running rugby so far. Keatley breaks up the late Irish move with a forward pass, knocked on by Tommy O'Donnell.

A roar from the Italian crowd - for the first time today - as they win a lineout, but the pressure doesn't last, Ireland being awarded the put-in at a scrum.

A Keatley kick is charged down and now Italy look to break. It falters quickly, and Ireland have regained the ball in their own half.

Ireland penalised for an early push on the scrum, just after the Italian front row had been given a stern talking to about their binding. All very niggly. Then another up-and-under causes more palpitations in the Italian backs, and Andrea Masi's knock on leaves Luke McLean offside. Penalty Ireland, Keatley to take... Sure, true, 6-0.

The disjointedness of Italy's play summed up as scrum-half Edoardo Gori picks up from a scrum, looks to kick, and can't because Biagi is in his way! Gori tries to burst down the blindside instead, and is pushed into touch.

Italy deal with that lineout well, and when Ireland are looking to break from halfway, Robbie Henshaw knocks on. Very typical passage of play, unfortunately.

Ireland win the lineout and begin to build for the first time in the match inside Italy's 22. Simon Zebo pushes forward, then Rory Best, then Jack McGrath. Recycle, recycle, recycle. Then Zebo holds on too long, and it's a penalty to Italy for not releasing. Joe Schmidt can't be happy with that.

A driving maul develops from the lineout. Best keeps ball in hand, it works wide to Murray, but he's dragged into touch. The referee brings them back for the maul being collapsed, and this is an easy attempt for Keatley for three points. Easy peasy, 9-0.

The crowd love that, but it's a big risk. Great take by Josh Furno at the lineout! Ireland penalised again for attacking the lifter and Paul O'Connell takes time to make his team's case while Peter O'Mahony receives treatment.

Ping, and Italy are on the board as time expires. Italy 3-9 Ireland - it hasn't been pretty, but it is setting itself up for a rousing second half.

Haimona gathers the kick-off, and Italy boot deep into Ireland territory.

For what feels like the first time in the match, Ireland string four passes together across the back line. It doesn't last, Ireland failing to release and Italy being gifted a penalty. "You must release quickly the ball," says the referee, as if that actually needs said. Penalties speak louder than words.

Key moment - for both sides. Keatley looks as though he might be setting up a terrific overlap opportunity, but Campagnaro guesses the play correctly and nearly intercepts it. If he had, all he had was grass between him and the try line.

This is as close as Ireland have been to the try line - Zebo to Payne to Henshaw, who is tackled, and then Ireland knock on. Really disappointing ending to a really promising move, which has been far too rare from Ireland so far.

Penalty to Italy as Ireland collapse the scrum. The pitch is not helping either side in the scrum, it must be said. It's a bit of a lottery as to who will infringe first.

'Fields of Athenry' does the rounds in the Stadio Olimpico. It's worth a shot, to see if there can be some inspiration for the defending champions.

Keatley, who had a ropey first few kicks from hand, has really settled into his first Six Nations match. That's another superb kick to touch, and the Italians have a lineout (a shortened one) just in front of their own 22. A semi chargedown by Jordi Murphy causes consternation, and Ireland are on the attack.

Knock on by Sarto as Keatley boots across field towards Zebo, and there's a penalty against Italy anyway for collapsing the maul. Keatley for goal again? Nope, Ireland go for the lineout. It's almost like they're challenging themselves out of their slumber.

Lineout, and O'Connell leaps supremely to take it. Is it a try? It is a try! Sweet relief, we have a try in this match! Conor Murray is the man who has bundled the ball over by a fraction, and it took all of 25 seconds playing against 14 men for Ireland to make their pressure tell. Conversion is good, it's game over.

Buses, it's like buses! There are tries everywhere all of a sudden! Tommy O'Donnell, who was not even supposed to be starting this game, makes the break from 45 metres and the 14 men of Italy are capitulating in dramatic fashion.

It never rains but it pours. It is literally teeming down in Rome now. Just what this pitch needed, really.

Knock on by Ireland around halfway. The ball is turning into a bar of soap, and Ireland should probably be thankful they scored their tries before this downpour arrived.

Andrea Manici steals the slippery ball at a lineout and this is a promising attack now for Italy. McLean looks outside, but there's nobody there as an Italian is down receiving treatment on the left wing. Good hands from McLean as the ball gets back to him in the 15th phase - and then Manici knocks on. A real shame for Italy after good recycling.

We're in to added time, a scrum five for Ireland, and this will likely get booted to touch as soon as they can. Ian Madigan does just that, and Ireland have a hard-earned win to get their Six Nations defence off to the start they wanted, if only the result rather than the performance.