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"In many respects, this is the defining game of the Six Nations."

Gerry Thornley made no attempts to quell the anticipation before Saturday's Six Nations match between Ireland and Wales.

There is much at stake for Joe Schmidt's side. Victory would galvanize Ireland ahead of away trips to Twickenham and the Stade de France, while defeat would be a tough blow at an embryonic stage of the tournament.

To build up to the weekend's crunch encounter, we were joined by Gerry and Keith Wood for Wednesday Night Rugby (on a Thursday after yesterday's excitment).

Keith thought Ireland were "efficient" against Scotland but failed to ignite the Aviva crowd.

But he believes that a win against Wales is far more important than the quality of the performance.

Gordon D'Arcy ©INPHO/Dan Sheridan

"We can't have a big performance and lose without there being changes to the personnel afterwards," he said.

As for the team, Gerry thinks Gordon D'Arcy's return to the starting XV is a boost because "there were a few glitches in the midfield and didn't seem quite as telepathic as it always is which is completely understandable. I think Brian O'Driscoll and Jonny Sexton will be more comfortable with him."

Gerry also analysed the strengths of Jamie Roberts who was their leading carrier and believes D'Arcy's involvement could help stymie his influence defensively.

But he believes it is a "hard game to call" and the "most difficult fixture to call over the last 30 years."

And Gerry thinks this current Welsh crop deserve more credit for their immense achievements over the last few years.

"They are a very proven, hard-edged side and it's going to take Ireland's best home performance of the tournament and perhaps Ireland's best performance of the tournament to beat them. But I think Ireland have a big game in them."

Keith also reckons Ireland's tempo will be much more intense than that witnessed against Scotland last week.

"I just think that the tempo Ireland will start with will be in stark contrast to last week. It will be difficult in the conditions. I have no issue whatsoever with the changes but I would still like to see Iain Henderson on the bench. He has the spark of something that I would like to see. I think he can be a game-changer," said Keith.

Image: Ireland's Cian Healy scores a try in last year's win in Cardiff ©INPHO/Dan Sheridan