However, it is hoped that all three will be available for selection and head coach Joe Schmidt said he is 'optimistic' about the three of them pulling through.
Sexton, who scored 25 points in a man-of-the-match display in the reverse fixture at Wembley Stadium in October, has accrued 42 points to date in this season's Heineken Cup.
Brian O'Driscoll, meanwhile, is currently in third place in the overall top try scorers' list in the Heineken Cup (28 tries), three behind Toulouse's Vincent Clerc and just one ahead of his provincial colleague Shane Horgan, who now lies in sixth place in the competition's all-time appearance list with 82 caps.
The Leinster team to face Saracens will be announced on Friday afternoon. The province currently top Pool 2 by five points, having won three of their opening four pool games.
Ticket sales for Saturday's match have already passed the 17,300 mark and are available to purchase online here, or from Spar (Donnybrook), the Leinster Rugby Store (Donnybrook), Champion Sports (Grafton Street) and Ticketmaster outlets nationwide.