Thats where mediation comes in.
Sure every contract is capable of mediation in the event of a dispute. However, every contract that I have ever negotiated clearly states who the arbitration body will be. Now Suarez has said that he wants to go to the Premiership and has the support of the PFA (for what that's worth). However if the contract states another arbiter must be used (eg Court of Arbitration for Sport) or a commercial court of arbitration then that is where it legally has to be heard irrespective of what Suarez wants.


. Christ, it's all getting a bit Brokeback Mountain.