​Borussia Dortmund winger Marco Reus has revealed his struggles at dealing with the news that teammate and best friend Mario Gotze was to join rivals Bayern Munich in 2013.

Gotze had established himself as one of Europe's most exciting talents with Dortmund, firing the club to two Bundesliga titles and even a Champions League final before deciding to leave the club in favour of their closest rivals.

Mario Goetze

​Reus, speaking to ​Goal and DAZN, admitted that hearing the news was tough to take, insisting that he felt ​Dortmund were ready to improve and dominate Europe before Gotze's departure.

He said: "I was at home, the doorbell rang and Mario was there. He told me personally that he will leave the club and take a different path. At that moment, I did not know what to think or say.

"I had come to Dortmund fresh and felt that we could be a good duo. Therefore, his decision was difficult for me to understand at the moment. We had a good squad for the years to come. And I actually had the feeling that we could have played even better.

Mario Gotze,Marco Reus

"I do not want to say I was angry, but of course you always want to play with the best players. When one of the best goes, that's difficult to understand. 

"In the end, everyone has to make their own decisions. You only have one career. And if that was the right decision for him then everybody has to accept that."

After struggling to make an impact with ​Bayern, Gotze ultimately opted to return to Dortmund in 2016, but the 27-year-old has battled fitness and injury concerns which have restricted his game time.

Mario Goetze

Despite these difficulties, Gotze proved to be a vital part of Dortmund's challenge for the ​Bundesliga title, racking up seven goals and seven assists as the club finished just two points behind Bayern.