Mats Hummels in a Bayern Munich shirt reduces Borussia Dortmund president to tears

Rauball is to stand for re-election at the Westphalian club's annual general meeting next week and, while looking to what he hopes will be a bright future, he could not help looking back at the loss of one of his favourite players.

"I have a very strong personal friendship with him and if I am honest, I have a few tears in my eyes when I think that he is no longer with us," Rauball told Kicker magazine.

Hummels returned to Bayern in July after spending eight years with Dortmund and making over 200 appearances for them.

He was part of their back-to-back title-winning teams in 2011 and 2012, and Rauball accepts it may be a while yet before the Bundesliga title returns to Dortmund, saying his club now have different objectives.

"We need to be qualifying for the Champions League every year," he said. "That would completely satisfy the sporting ambitions of my next term, assuming I am re-elected."

Rauball believes coach Thomas Tuchel is the right man to guide them to that, praising his "exceptional work" and giving him his "unreserved backing" to continue the way he is going.

"He is very creative in the development of new playing styles and he keeps on surprising you, like with the success he's getting out of Raphael Guerreiro in a position which nobody would have predicted him playing (midfield, rather than his previous left-back role), and for other players too," Rauball said.