The pair are struggling after suffering a back spasm and calf strain respectively, with Leicester Tigers utility-back Geordan Murphy and Ulster front-rower Bryan Young having been brought into the Irish squad in case they do not make it in time.

Denis trained this morning and everything seemed fine, but obviously the problem with a back spasm is that it could go backwards again and if it does we could be in trouble, said OSullivan.

Well just have to see how he goes in the warm-up and I think well leave it to the last minute to be 100% sure.

Marcus Horan was just warming up and he felt a tightness at the top of the calf, which is a little bit of concern given that it is only 24 hours out.

I prefer to call these things earlier than later but in this scenario you always give the guys every opportunity.

While Ireland, flying high after a spectacular victory over England a fortnight ago, will be aiming to claim the Triple Crown on Saturday, Scotland will be looking to salvage some pride after a 37-17 humbling by Italy.

However, OSullivan said that it would be dangerous to read too much into the background of this match.

You buy into that stuff and it will be your downfall. The one thing we know about Test rugby is that all the talk that goes on before the match might be very interesting, but when the ball is kicked off nobody knows what is going to happen, he said.

If you are going to depend on the past to win the game tomorrow then you are in big trouble.

This Scottish team have a point to prove and we know that is all Scotland need  they have shown many times in the past that they are very good at proving points.

And weve gone into games before where weve been favourites but been turned over because we probably bought into our own fame too much.