Juve were impressive 2-0 winners in Wednesday night's Champions League tie.
Buffon said on Radio DeeJay: "I watched the match last night and I saw encouraging signs. Thiago Motta showed that he is truly destined to start a new journey with us. It was needed. In addition, some players also gave positive signs.
"(Michele) Di Gregorio made a truly exceptional and fundamental save (against Erling Haaland). If they had conceded a goal, it would have been difficult to recover. It is better not to compare the two goalkeepers.
"(Wojciech) Szczesny's career is already what it is. Di Gregorio is young, so we will see how his career develops in the future. The two goalkeepers have different characteristics, and this seems to have been one of the factors that influenced the choice. At least according to what has been reported."
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