Lorenzo Insigne's first-half opener for Napoli was cancelled out by Mario Rui's own goal in the second half.

The Italians looked to be heading for victory after Dries Mertens struck but Di Maria secured a point at the death.

The result means Liverpool overtake Napoli and go top of Group C after they beat Red Star Belgrade 4-0.

Napoli had the better of the first half and deservedly took the lead on 29 minutes when Insigne smartly converted Jose Callejon's through ball.

But PSG were much improved after the break and equalised when Thomas Meunier's low cross deflected in off visiting defender Rui.

Napoli, who lost Insigne to injury, went ahead again with 13 minutes left when Mertens pounced on a loose ball to score from close range.

Defeat would have left PSG with just three points from three games but in the third minute of stoppage time, former Manchester United and Real Madrid winger Di Maria curled the ball into the top corner from the edge of the box.

Henry waits for first win

Monaco drew 1-1 away to Club Brugge in Thierry Henry's second game in charge as both sides secured their first point in Group A.

Monaco took the lead on 31 minutes through 18-year-old Moussa Sylla and Brazilian forward Wesley levelled for the hosts before half-time to keep Henry waiting for his first win as a manager.

Porto went two points clear at the top of Group D after a 3-1 win at Lokomotiv Moscow, with Moussa Marega's penalty being followed up by Hector Herrera and Jesus Corona goals for the Portuguese champions.

Porto's ex-Real Madrid goalkeeper Iker Casillas saved a Manuel Fernandes penalty at 0-0 while Anton Miranchuk pulled a goal back to make it 2-1 but the Russian side, who had Solomon Kvirkvelia sent off late on, stay bottom and without a point.

Schalke remain second in the group, a point ahead of Galatasaray, after a goalless draw between the sides in Istanbul.