A late header from the Brazilian served to spare the hosts' blushes but they are still waiting on the title
Victory would have made winning their first title in 19 years a formality but they were to be denied by a first-half goal from Gael Danic, followed by referee Castro’s controversial decision to send off home captain Thiago Silva at the end of the opening 45 minutes.
Alex did head a late leveller for the 10-man hosts, who at least saved some face by avoiding defeat, even if they will have to wait at least one more week for the title.
PSG made a nervy start to the game that was capped by the opening goal from Danic after 17 minutes. Vincent Aboubakar was given far too much room to fire a shot at goal, which Nicolas Douchez could only parry into the path of the winger, who finished with ease.
To make matters worse for Carlo Ancelotti’s side, Thiago Silva was dismissed just before break for a rather benign pull on the referee’s elbow as he tried to get the official’s attention.
It seemed that the hosts were to be frustrated yet Alex headed them level with little over five minutes remaining.
Valenciennes had started the evening like they wanted to spoil the capital side’s party. Danic, in particular, had been threatening even prior to the opening goal and had not only tested Douchez himself, but also fired in a wicked first-minute free kick that Lindsay Rose headed just past.
The home side had replied primarily through Ibrahimovic, who was over-elaborate with a flicked finish after lofting the ball over Nicolas Penneteau in the visiting goal.
Valenciennes’ goalkeeper was to have a big role in this match and made a smart stop from Javier Pastore shortly before Danic silenced Parc des Princes.
In the immediate aftermath of the goal, Ibrahimovic released Ezequiel Lavezzi with a fine pass but the Argentine was thwarted by the keeper. Several other chances would be squandered before the break, with Thiago Silva twice going close before he was dismissed.
Going down to 10 men winded the hosts at the beginning of the second period but they mustered a great siege on the Valenciennes goal in the second period. Pennteau was again immaculate, though, making fine blocks from Pastore and Alex after watching Ibrahimovic shoot agonisingly wide following a moment of magic from the Swede.
Valenciennes could not hold out, however, with Alex finally drawing the hosts level with a thumping header.
Having missed their chance to secure the Championnat title, PSG now face a very tricky trip to Olympique Lyonnais next Sunday as they attempt to lift their first league crown in 19 years. A win at Stade Gerland will secure the long-awaited title.