Bayern Munich remain confident of landing versatile Spain international Javi Martinez from Athletic Bilbao despite complications arising in negotiations between the two clubs.
Martinez, 23, has a release clause of around €40 million in his Athletic contract, which would set a new transfer record in Germany were Bayern to meet it.
However, the transfer appears to have hit stumbling block with Bavarians chairman Karl-Heinz Rummeninge claiming that there are still "some tax and legal problems" to be resolved.
However, Rummeninge still believes the transfer of Martinez to the Allianz Arena will go through.
"This is not a normal transfer, I might have to explain again," Rummeninge told Sky Sport. "In Spain every player has a release clause in his contract. Martinez has one over €40 million.
"It seems like the Basques are not only proud but also complicated. There are still some tax and legal problems to be sorted out. Once this is done, the transfer will be finalised.
"Bilbao's chairman is preparing for an election this autumn and maybe he does not want to do anything wrong. Those clauses can be legally complicated, and this needs sorting out. Lawyers are on it now."
Despite the saga, Bayern's management remains "utterly positive" about Martinez, who is being targeted to add new depth and creativity to the Bayern midfield. The wantaway star had already offered to accept a cut in his annual salary to make the transfer happen.