Sancho has arrived on-loan from Manchester United.
"When I saw they had signed Jadon Sancho on Deadline Day, I wondered if there was even any shirt numbers left for him," he told BetVictor and Football.London.
"Imagine him opening the door to the dressing room and seeing so many players they don't all fit in the same dressing room! At the training ground they must have two dressing rooms, three pitches and 12 physios.
“The club are not the only ones responsible for the situation. It also comes down to the players. How can Sancho bring himself to sign for Chelsea after what happened at Manchester United? He was loaned to Borussia Dortmund, then went back to United, and now he’s off to Chelsea who have 40 or so players and he is just one of them."
Petit continued: "Hasn't he had enough of moving around clubs, losing his way on the pitch and losing his confidence? Now he's at a club that has no consistency, lacking in confidence and results. If he's not there for the money, what is he there for?"