I was also surprised by the result of the match. Even though the biggest blame is Szczesny, I think it's the team's fault. Allegri said that their team lost focus because they conceded first. I also saw that the Juventus players were surprised when Lauriente scored a quick goal and that was the difference in this match.
Actually, there were many differences in this match and one of them was the own goal scored by both teams in that match. However, on the one hand, I was also surprised by the defeat experienced by Juventus at home to Sassuolo with that amount of score, even though Juventus were able to equalize in the second half when Federico Chiesa scored a goal for Juventus. But what was very surprising was the own goal at the end of the match which was clearly very profitable for Sassuolo even though Sassuolo could also have won without the own goal.