Marcelo Bielsa says Marseille must be patient if they are to break down a well-organised Nantes defence in Ligue 1 this weekend.
The league leaders have the chance to open up a four-point lead over Paris Saint-Germain with victory in Friday's game, as their title rivals do not play until Saturday.
Fourth-placed Nantes are likely to present a stiff challenge, however, having conceded only nine league goals so far this season - fewer than any other side.
Nantes kept a sixth clean sheet in 14 matches last weekend when drawing 0-0 with Saint-Etienne and Bielsa has been analysing them closely to try and find a way through.
"This is a team that defends very well, it is the best defence in Ligue 1," he said.
"This is a team that knows how to play in its own half and is comfortable to defend in front of their goalkeeper. They pass quickly from the defence, [and] do not need a lot of passes to attack."
Marseille can take confidence from the fact they have won their last six matches at the Stade Velodrome.
However, they did not manage to beat Nantes last season, losing at home and only taking a point from the return fixture.comments