Blanc: Chelsea focus affected us
The sides will meet in the last eight of the competition after being drawn together on Friday - hours before PSG continued their march to the Ligue 1 title with a scrappy 1-0 win over Lorient.
Although PSG lead Monaco by 11 points, having played a game more than Claudio Ranieri's men, Blanc has warned his squad not to take anything for granted.
He also believes interest in the tie with Chelsea proved an unwelcome distraction ahead of the Lorient game.
"I would say the players weren't thinking about Chelsea but all the journalists we came across talked only about that and it made it difficult to think about Lorient," he said.
"We've done really good things since the start of the season but we've won nothing yet."
Monaco can close the gap between themselves and PSG to eight points with victory over Lille on Sunday, as they look to keep their faint title hopes alive.
Although his side were not at their best against Lorient, Blanc was pleased to see PSG return to the capital with three points.
"We can't expect to win every game three, four or five-nil. We got the win though and I need to congratulate my players, even if they weren't extraordinary," he added.
"We need to keep improving on our records and I hope we'll win trophies come the end of the season."