France retained their crown on points difference alone with a dubious late try from Elvis Vermeulen, awarded by the television match official, edging them past Ireland.

O'Sullivan believes the decision to allow the try was an example of Ireland's lack of fortune during the championship.

'We thought we had won the Six Nations until the final seconds in Paris. It was a tough, emotional tournament,' said the Ireland coach.

'I've always said the Six Nations is a tough competition to win. You need to play well and be lucky with injuries, which overall we were as we kept a pretty healthy profile.

'But you also need the rub of the green at some point in the tournament. People say you make your own luck but we could say hand on heart that luck wasn't on our side on Saturday.

'We didn't get a lot of luck in the Six Nations so I hope we get some in the World Cup.'

Ireland put themselves in a magnificent position to clinch the title with a spellbinding 51-24 victory at the Stadio Flaminio that saw Italy cut to ribbons.

And while Irish title hopes were ultimately dashed by the narrowest of margins, O'Sullivan feels the display in Rome will stand the team in good stead for the summer tour to Argentina and World Cup.

'Our performance sent a message out because our accuracy was right up there. We did create a lot of chances and took them,' he said.

'In the first half we managed to get three tries without having the best possession.

'There was a lot of good in that and we have to take a step back and say that it was a good performance against Italy.

'They were on a high after taking two big scalps but we put them to the sword in a pretty clinical way. That's got to carry some weight.

'Now we have to keep that momentum and kick on.'