FC Bayern Munich have been working tirelessly in the off-season to ensure they can again approach a Bundesliga season as title favourites.

But the jury is still out on whether they have spent their money wisely.

The 26-time German champions have most recently splashed out an initial fee of 35 million Euros on Portuguese star Renato Sanches, however, that amount could eventually rise to 80 million Euros based on performance-related bonuses worked into the deal.

Sanches joins new signings Mats Hummels, Niklas Dorsch and Fabian Benko at the club, while Mario Gotze, Sebastian Rode, Medhi Benatia, Serdar Tasci and Ivan Lucic have been shipped out.

Bayern Chairman Karl-Heinz Rummenigge and boss Carlo Ancelotti both felt justified in spending such a huge amount on a player as young and untested as Sanches. However, his stand-out performances at the 2016 European Championship, where Portugal romped to the title, with Sanches being named Young Player of the Tournament, may have alleviated some fears over the hefty transfer fee.

Rummenigge told Bild: “This is a tremendous amount of money, something we do not need to discuss, but I sat down with Carlo Ancelotti in March and we agreed: this player is worth the risk.

“At the European Championship it has already been seen what tremendous power he brings, and what a personality he is on the pitch at 18. That’s impressive.

“When Renato Sanches became known at the European Championships, he had already signed with us.

“We won [the race for his signature] because the others had just planned their holidays.”

With Borussia Dortmund having also flexed their muscles in the transfer market this summer, snapping up Andre Schurrle and Gotze, along with a few other lesser known players, Rummenigge did admit that the eight-time German champions would continue to be their biggest rivals this season.

He added: “They have a good philosophy and will be our natural competitor.

“It is no coincidence that Dortmund has continually established itself, and it is also proof that football is not exclusively about money, but also good work.

“The conditions were better at other locations, but in Dortmund they have worked better.”

Bayern are at 1/10 to win the league with BetVictor, with Dortmund handed odds of 6/1 to wrestle the league crown from the clutches of the Bavarians.