Monaco have survived a number of threats to reach the half-time interval on level terms with Paris Saint-Germain at the Stade Louis II.
The visitors came agonisingly close to breaking the deadlock when a corner reached Marco Verratti at the back post, but the Italian midfielder was unable to climb high enough to add the finishing touch.
Ezequiel Lavezzi then carved out an opening for Edinson Cavani, who used some space in the box to force Danijel Subasic into a fine save.
Laurent Blanc's side were in full control midway through the opening 45 minutes, but another clear chance was wasted when Lavezzi flicked the ball wide after Blaise Matuidi had won possession in a congested box.
