The loss to lowly Strasbourg is PSG’s first loss in all competitions, with Nuno and Bahoken scoring on either side of Mbappe’s equaliser.
PSG held 73 percent of possession and 29 chances, but could do little to win and Pastore believes it should serve as a wake up call.
“Strasbourg had two chances,” said the midfielder. “We weren’t at 100 per cent from the start. We tried but we weren’t able to score the second goal.
“It’s no accident; it’s because they were very good. They had a very good defence.
“The goal is to finish first at the end of the campaign. We’ve taken a knock that will help us for the future.
“Today, we paid dearly for two moments for which we weren’t focused.”