Following the weekend's Celtic League matches, O'Sullivan will consult with his management team before deciding on the make up of the side.
O'Sullivan himself was in Eugene Cross Park on Friday night to see Ulster in action against Ebbw Vale and the following day he was among the large attendance at Stradey Park where Munster opened their account with an impresive win over Llanelli.
He will have been impressed with the performance of out-half Ronan O'Gara who was back to near his sparkling best, landing five penalties from five attempts and controlling a game that Munster won 20-13.
Assistant coach Declan Kidney was in Selkirk to witness Connacht'slast gasp (28-27) victory over Borders, while team manager Brian O'Brien was in Donnybrook where Leinster came from being 15-5 down to win 31-18. O'Brien will have learned little that he didn't know already about Brian O'Driscoll or Denis Hickie - both class acts - but he will have noted the performance of Eric Miller who had a marvellous game.
The side will be announced at 12 noon (approx) tomorrow (Tuesday).