context: From the age of 3, he is fond of football, played in the youth clubs “Ronsberg”, Eintracht Hombruch and Borussia (Dortmund), in which he made his debut in the first team in 2008. After spending five years at the base of the Ruhr club, in the summer of 2013 he moved to Bayern Munich for € 37.0 million, making him the second most expensive German player in history, after Mesut Ozil (€ 50 million) [4]. For five years in Dortmund, Götze won two league titles and one Cup of the country, and also became a finalist of the UEFA Champions League 2012/2013. With Bayern Mario won the German Championship three times in a row, became the winner of the Club World Cup, and also won the UEFA Super Cup and two German Cups.
question: When did the German footballer Mario Götze start playing for Dortmund Borussia?
answers.text: 2008