The secret behind Borussia Dortmund's success? Books

Defender Mats Hummels reveals that Borussia Dortmund's players have been given books by their manager, Thomas Tuchel, to give them a different perspective on sport.

Dortmund have won three times as many matches compared to the same point last season and Hummels, 27, admits he's enjoying his latest read. He said: "It was from a basketball coach's point of view and looked at how to handle the team, how to focus on details and how to stop different problems developing."

This clip was taken from 5 live Sport on 25 January 2016.