Former Bayern Munich midfielder Dietmar Hamann has declared Robert Lewandowski did the club a "huge favour" by making it clear he wanted to join Barcelona.

The Poland international this month completed a €50million move to the Catalan giants, bringing an end to his trophy-laden stint in Germany.

Bayern were initially adamant that Lewandowski would not be allowed to leave, despite being in the final year of his contract, but the prolific striker was determined to move to Barca.

The 34-year-old eventually got his wish and Hamann believes Lewandowski helped the Bundesliga champions get a great deal when they sold him due to the way he went about his business with a "distasteful" approach.

"I think they are happy that he has gone. This whirlwind of signings began and he made some statements," he told Sky Germany.

"It has to be said that Bayern behaved very well and very professionally. Lewandowski did [Bayern] a huge favour with his statements.

"Without them, [Bayern] probably never would have been able to get the price that they obtained. As distasteful as his exit was, Lewandowski did Bayern a huge favour."

Lewandowski this week made his Barca debut in a pre-season victory over Real Madrid in Las Vegas.

Xavi's side begin the new LaLiga season at home to Rayo Vallecano on August 13.