The Dutch winger, 25 left Hamburg for Antonio Conte's Juve side a year ago, but played only four times in Serie A as the Turin club captured the Italian title.
“Every player was entitled to a new Ferrari or a €200,000 bonus after we won the championship,” said the former Ajax player, who has returned to Germany with Bremen in a 5.5 million Euros transfer.
“However, Juventus forced me to renounce that right before they allowed me to join Bremen.
“Coach Antonio Conte never spoke to me. He did not utter a single word to me all year. He completely ignored me.
“I have never ever experienced anything like that. It was very frustrating for me.”