The Welsh romped to their first championship clean sweep since 1978 with a crushing 32-20 victory over an outclassed and disappointing Irish outfit at the Millennium Stadium on Saturday.

OSullivan applauds Wales progress but anticipates the next challenge for Mike Ruddocks men is to continue winning when rivals are gunning to unseat the new kingpins of northern hemisphere rugby.

Wales have something good going at the moment. Their lower age teams are coming through well so maybe they have got it right by changing their structure so quickly, he said.

But its a fickle business - you can go from hero to zero in a couple of weeks and back again. Theyve been on a good run but the next year will be hard because everyone will put on the war gloves for Wales.

Theyre now the team to beat and inevitably that will make life tough for them. But at the moment theyve got it right and theyre worthy Grand Slam champions.

It left OSullivan wondering what might have been had Leinster pair Gordon DArcy and Shane Horgan been fit for the last two games of the championship and there is no doubt their loss was a significant blow.

We went into the Six Nations in pretty good nick after the autumn internationals, but we only had a clean bill of health for about 20 minutes, said the Ireland boss.

If I was to look back over the championship my wish would be not to lose my midfield for the championship. We started the first four games with four different centre partnerships.

Against Wales was the first time we could field the same midfield for consecutive matches. If those people who made us favourites knew that would happen before the tournament began, they might have changed their tune a bit us.

The losses put pressure on our forwards. We have a good pack but they have been forced to carry more of the workload and that affected the way we play the game. We fit our gameplan to the players we have, so the dynamics changed.

Other teams have had injuries, but they seemed to have been able to cope with that a bit better. They have more guys coming through in those key areas.

Having said that, with five minutes left in Dublin nine days ago we were still in with a Grand Slam chance against France. Suddenly you lose that, then you lose again against Wales and it becomes a bad championship.