The 43-year-old saved a penalty early on and helped the Bianconeri during a hard-fought 3-1 win at the Mapei Stadium.
“I don't know if the penalty save was decisive, maybe the team would have recovered anyway. It certainly helped us a little more," Buffon told Juventus TV.
“Tonight we secured a desired, sought-after win. From suffering and humility. If you arrive in this stadium against Sassuolo and think of being superficial, you will get a nice hairdo."
Buffon has confirmed he will leave Juventus for good after the end of this season.
“It was a very good second experience at Juve," he continued. “In the end I wanted to test myself as a man too.
“Accepting, even at 41, to start as second choice, is the total demonstration of my respect for Juventus. I have always been supportive.
“This was asked of me and I did it, because I love Juventus and all my teammates.
“This was my exam to show what kind of affability I can give as a person. Every now and then you must create the stimuli yourself.
“I have always done that, otherwise I wouldn't have the motivation to continue playing. The lads trust me and in the end I wanted to test myself, because I was never the second choice and I had never been on the bench.
“I wanted to weigh myself in this role and I'm happy because I responded as I should, I know I can trust myself."