The French boss may have to shuffle his pack for his side's first European tie of the campaign with doubts lingering over several players.
The Greek and French champions meet on Tuesday night in Group C as Paris Saint-Germain and Olympiakos begin their respective Champions League campaigns.
PSG will take heart from the fact that the club reached the quarterfinals last season, where it was knocked out by Barcelona over two legs.
Over the summer coach Carlo Ancelotti departed for Real Madrid and was replaced by Laurent Blanc and the former France boss has wasted little time in continuing the club's big-spending transfer policy.
Edinson Cavani, Marquinhos and Lucas Digne have all arrived in the French capital and PSG has started the season well, winning three of its five league matches and drawing the other two.
Injury doubts over Alex (thigh), Jeremy Menez (back) and Javier Pastore (foot) mean Blanc may have to shuffle his pack for the trip to Greece.
Olympiakos won three games in the group stage of last season's Champions League, including two victories over Ligue 1 outfit Montpellier, but still failed to advance to the knockout rounds.After a busy close season, Olympiakos' squad is barely recognizable, with Javier Saviola and Vladimir Weiss headlining a host of summer signings, as just eight of last season's Champions League squad make the cut this time around.