Avram Grant is determined not to underestimate Olympiakos after Chelsea were drawn against the Greek club in the last 16 of the Champions League.
Grant's side will be heavy favourites to progress to the quarter-finals for the third time in four years.
But the Greeks won home and away against German side Werder Bremen as they qualified from a group also featuring Real Madrid.
So the Chelsea manager is counselling caution.
"Olympiakos did well in the group stage. They won against Werder Bremen home and away and Lazio, so it is not an easy game," Jose Mourinho's successor at Stamford Bridge said after Friday's draw.
"They are a good team. On paper we have a good chance but first we need to qualify for the next round and then speak about it."
Olympiakos boss Takis Lemonis knows his side face a tough task to knock out the team with the best defensive record in the competition.
"The draw is a very difficult one, as it would have been with any other opponent," he said.
"It's much too early to judge how the games will go because we have two months before these matches. A lot of things will be judged better when we see what situation we and Chelsea are in at the time. We knew that whichever team we faced at this stage would provide a very difficult challenge.
"At this level there is no good or bad draw. We hope that we will be in a good situation when the time comes."