Irish opt to close the roof - Best
Ireland will find out later tonight whether their decision to agree to close over the roof of The Principality is the right one.
The scattered showers forecast for the occasion was the deciding factor for Ireland captain Rory Best and out-half Jonathan Sexton.
"It was purely a rugby decision," said Best.
"When you ask kickers and throwers if they want to take the weather out of the equation, I wouldn't say it was an easy decision. That was the real reason for us as players."
"If the weather forecast had been dry, we'd probably have left it open."
Of course, it will heighten the atmosphere, possibly handing Wales an advantage in the final quarter when bodies tire and minds reach for any edge to keep going.
"We're looking forward to the challenge and the atmosphere," said Best.
Forwards coach Robin McBryde has forecast a ferocious response from Wales after a hail of criticism that has followed coach Rob Howley's decision to make no changes.
"I think each individual deals with it differently. If you go looking for it, you're going to find the criticism," said McBryde.
"As far as I'm concerned, when you're taking part in international rugby as a player and a coach, you're always under constant pressure."