Injured Zlatan Ibrahimovic has been ruled out of action for an unspecified amount of time but he will be available to finish the season, Paris St Germain coach Laurent Blanc said on Friday.

"He has a muscular lesion. He is unavailable for the coming weeks for an unspecified amount of time," Blanc told a news conference ahead of his team's Ligue 1 home game against Stade Reims on Saturday.

PSG lead second-placed Monaco by 13 points with seven games left.

"Unless the injury gets worse, he will be available to finish the season," added the former Francecoach.

"It's hard to tell because it's still fresh, it will depend on how the injury evolves."

Sweden striker Ibrahimovic was substituted midway through the second half holding his thigh in PSG's 3-1 home win against Chelsea in the Champions League quarterfinal first leg on Wednesday.

He will definitely be out of Tuesday's return leg at Stamford Bridge but it remains unclear whether he will be fit for a possible semifinal should PSG successfully defend their advantage.

Ibrahimovic's absence, however, will not change much in London, according to Blanc.

"Our philosophy and our tactics will not change," he said

Edinson Cavani is set to take over in the No 9 position with Brazil centre Lucas likely to be fielded on the right flank, the position usually occupied by the Uruguay forward.

"Lucas is a very fast player, he must improve his movements to be very dangerous," said Blanc.

"He can dribble fantastically but he has to be more collective. I know he will improve."