Lewandowski will be heading into the final year of his contract at the Allianz Arena and yet is decided on whether or not he will extend.
Barcelona have been heavily linked with the Bundesliga top scorer, witth coach Xavi Hernandez looking to bolster his squad with a prolific goal scorer.
Former Bayern midfielder Javi Martinez claims Lewandowski feels he would have won a Ballon d'Or by now if he was playing in Spain.
"Just today I spoke to him. He told me: 'Every day you have more grey hair'. Bayern's issue is that there is no clause. If they don't want to sell you, you're screwed," Martinez told El Larguero.
"I think that there is some possibility. I think he believes that by playing in Spain he would have had a Ballon d'Or or two. And that's why he wants to try.
"He has the feeling that he deserved the Ballon d'Or. It's not the same to play in the Spanish league, in Barca or Madrid, as it is in the German league."