The Irish coach has put the hamstring-stricken duo on a 24-hour rehabilitation plan in a bid to race them back to fitness for Saturday's RBS 6 Nations sell-out clash at Murrayfield.

And while Williams, who coached both players to Celtic League success at Leinster in 2002, may point to their inclusion in yesterday's Ireland squad as little more than mind games, an upbeat O'Sullivan has insisted their odds on recovering are ''reasonable''.

O'Sullivan, hoping for a fifth straight win over the Scots, said: ''They both have a chance of making it, otherwise we would not be naming them in the squad.They both have mild strains, not tears.

''The doctors have got to be pretty happy that they are going to come through and if they are not - we will not risk them.

''There is a possibility that a mild strain could become a tear so it is a nightmare situation for a coach really.

''But it is how you manage these things that really counts. We have our rehab specialist Brian Green working with them 24-7.

''The good thing is that we can work on them and the more we do - the quicker they can recover.''

Their inclusion would certainly make O'Sullivan's 40th game at the helm an easier ride in Edinburgh, against what he expects to be a Scottish side with a lot to play for.

''Scotland changed their defence from the autumn to a more aggressive one against the French,'' O'Sullivan added.

''I think it paid off and they would have been disappointed they did not take more advantage of what was a poor French display. Scottish heads will not be down though. They did a lot of good things.

''They held onto the ball very well. They used the corners very well to keep the ball behind France, and they had a very good lineout - they always have had.''