Paris Saint-Germain coach Laurent Blanc has admitted that a hamstring injury suffered by midfielder Blaise Matuidi "does not look good" with a crunch Champions League clash with Chelsea less than a week away.

Matuidi came off in the second half of Wednesday's 3-1 French Cup quarter-final win away to Saint-Etienne feeling his hamstring.

Blanc said at the time the substitution was a precautionary measure but with the Champions League last 16, second leg against Chelsea to come next Wednesday it was always going to be a race against time for the player to recover.

"I am worried when a player comes off with a sore hamstring. He has undergone tests (on Thursday) and he is having more," said Blanc.

"We will keep a close eye on it. It is never a good sign, I won't lie. But we will see how serious it is and if we can get him back, not for tomorrow (Saturday) but for Chelsea."

Ligue 1 leaders PSG entertain Montpellier on Saturday with Marco Verratti set to again miss out but Angel Di Maria likely to return after missing the Saint-Etienne win and last week's defeat at Lyon, which was their first domestic defeat since March last year.

Paris will go to London defending a 2-1 lead from the first leg against Chelsea.