The Parisians were trailing by a goal when the Brazilian was dismissed but earned a 2-2 draw on the south coast thanks to Edinson Cavani's superb late free-kick.
In the first half, Neymar had scored to cancel out Luiz Gustavo's opener before Florian Thauvin restored the lead after the break.
WHY WAS NEYMAR SENT OFF?
Neymar was shown a second yellow card after a coming together with Lucas Ocampos.
He had already been fouled when Ocampos tripped him again to bring him down, leading Neymar to react angrily by barging into the Argentine.
Having already been booked for a foul on Morgan Sanson, the world's most expensive player was carded again for that reaction and subsequently received his marching orders.
Ocampos was also booked for the trip on Neymar.
WILL PSG APPEAL THE RED CARD?
PSG are unlikely to be able to appeal the decision - and its subsequent suspension - as Neymar received two yellows rather than a straight red.
Ligue 1's disciplinary committee meets every Thursday and it is expected Neymar will be handed an automatic one-game ban that with this offence.
That doesn't mean PSG are happy about it, though.
Neymar was fouled four times during the game, more than any other player - and many in the Parisian camp would argue that more went unpunished.
"If I had been in Neymar's shoes I would have lost it 15, 20 minutes before he did," Marco Verratti said.
Ocampos has also been accused of exaggerating the contact between himself and Neymar when the Brazilian reacted to being fouled by barging into him.
"I think it was exaggerated, yes," Neymar told Esporte Interativo. "And unfair. I spent the whole game getting enough. I have many marks on my body.
"The yellow card, I think it's not fair to Neymar," Unai Emery added.
"He's a player who wants to play, but if every game he is provoked, [there is] aggression... I think it's a job to protect the important players in both teams."
WHAT GAMES WILL NEYMAR MISS?
Assuming he is given a one-game ban, Neymar will miss PSG's home match against Nice on Friday.
Nice, who sit 14th in Ligue 1, lost a fourth game in a row in all competitions at the weekend to Strasbourg, and were missing top scorer Mario Balotelli due to injury.