PSG settles for goalless Ligue 1 draw
The visitors had Ezequiel Lavezzi sent off, while boss Carlo Ancelotti himself saw red in what was another frustrating night for the big-spending side from the capital who deserved no more than the point they left with.
Ajaccio were well organised and stubborn at the back, limiting the away side to few chances.
The hosts had to do without Mehdi Mostefa, who was sent off in their 1-0 opening day win at Nice, with Johan Cavalli his replacement.
The visitors, who had not won in their last six matches at the Stade Francois Coty, were without Zlatan Ibrahimovic who had a foot injury, with Nene coming in while Thiago Silva remained absent.
It meant that Ancelotti kept faith with the same back four who were roundly criticized in last week's 2-2 draw with Lorient.
The Parisians did have Javier Pastore back from suspension and it was the Argentinean who provided the one moment of quality in the first half.
The playmaker curled a delightful through ball to Nene down the right and Ibrahimovich's replacement crossed into the path of Jeremy Menez, who unchallenged from six yards, shot straight at Guillermo Ochoa in the home goal.
Ajaccio had the first chance of the second half as a mistake from Mamadou Sakho was pounced upon by last week's goalscorer Eduardo who on the right hand side shot across goalkeeper Salvatore Sirigu and onto the post.
PSG had to play the last half hour with 10 men after Lavezzi went in two footed on Benjamin Andre and rightfully saw red.
Ancelotti joined his summer signing in the stands in the closing minutes after kicking a water bottle onto the pitch as PSG left Corsica with just a point.