Sancho had returned late from international duty with the England squad and was dropped for the win over Borussia Monchengladbach.
"We did not make the decision easily, but it was without alternative. Sancho is an excellent player, but we have a responsibility for the club, for the spirit in the team," said Zorc.
BVB coach Lucien Favre also spoke of the former Manchester City winger: "Jadon is a great player, not a discussion. But he still has a lot to learn. He must continue to enjoy training and progress."