The 67-year-old coach was full of praise for the versatile midfielder, but underlined that his side will not break the bank to sign the Spaniard
The Bundesliga giants have publicly admitted that they are interested in signing the Spain international, who is also being courted by Barcelona.
However, Bayern CEO Karl-Heinz Rummenigge has stated that he is not prepared to meet Martinez's €40 million asking price, but Heynckes says a deal could be struck if the Basques lower their valuation for the player.
"Javi Martinez is a great guy, he has a strong character and he is a great player," Heynckes told reporters. "He has not finished his development yet. He has a market value of €22-23m. Athletic's asking price? I think it is indecent."
Rummenigge also revealed that Barcelona, who are also reported to be interested in the player, were not willing to pay the full €40m to secure Martinez's signature.
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