Athletic can pay 20 million for Javi Martínez without any problem. (The club) has the capacity to handle this type of addition. There would be no problem handling the payment from an economic point of view.
At 30, Martinez is versatile and stable, but could be considered expendable by some as Bayern’s roster evolves. Back in January, Athletic Bilbao stated its initial interest in bringing back Martinez, but since that time Martinez has been excellent for Bayern. In February, Martinez publicly stated his intentions to stay with Bayern and multiple outlets indicated that Martinez would not be a part of the rumored roster shake-up.
Even with his recent stellar performances, however, the Bavarians might be ready to move on. Given that Joshua Kimmich is also now going public with his desire to play a defensive midfield role as well, it might be a good time for Bayern to think about a sale of Martinez.