At which point, the Italian didn't have his future confirmed for 2020, although the next week at Monza in his home race he came through to finish in ninth.
"It was a big shock to everyone in the team [that he crashed] because we had a chance of a good result," Vasseur said to GPUpdate.net.
"Antonio came back strong and in one of the last laps, that crash took place. We then had a serious conversation with him, because things like this can determine your career.
"We thought about the future and had to meet the following week sit down to discuss the situation. His response was very good."
In his first full season in F1, the 26-year-old finished 17th in the final drivers' standings on 14 points.