Chelsea manager Jose Mourinho has warned his players to play with their heads as well as their hearts, when they Paris Saint-Germain tonight.

Mourinho led Porto to the European crown last and the Portuguese coach believes the mental approach is a crucial factor in a team’s success.

“One of the secrets to success is to have a tactical culture which helps you adapt,” he said.

“To play a French side is not the same as playing an Italian side or a Spanish side. The players must be able to think for themselves on the pitch and not just play with their hearts or how the opposition want them to play. Emotions have to be kept in check.”

PSG coach Vahid Halihodzic, who has seen his side struggle domestically, was in cautious mood ahead of the match.

“A draw would be a good result given the start to the season we’ve had,” he said.

“They do not concede many goals and it is difficult to play on the counterattack against them. We will have to get it right defensively before we even think about attacking.”

Halihodzic is without suspended Colombian central defender Mario Yepes, but forward Danijel Ljuboja and full-back Bernard Mendy are available again after injury.

Mourinho, is without goalkeeper Carlo Cudicini, full-back Celestine Babayaro and winger Arjen Robben, is looking for a win tonight.

“We are not here to play defensively,” he said.

“We are solid, compact and hard to beat. But we have also played good attacking football this season and we have enough quality to score goals away from home. We have six group matches and we will play to win them all.”

“Teams raise their game for the Champions League. I know PSG are well organised and it helps them that they have largely the same same squad of players as last season and the same coach. And signing Jerome Rothen adds some real quality. He’s a fantastic crosser of a ball.”