Coolen told the club yesterday that he "would no longer provide his services", according to Adelaide United today.

As a result, the Reds board ripped up his contract, effective immediately.

Now Coolen has hired solicitors and will be taking his case to the FFA and has invoked a grievance procedure with the governing body.

Adelaide United today insisted there was no case to answer and added: "Adelaide United FC regrets that Coolen has chosen not to continue his employment with the club."

Coolen was axed from his position as head coach over the weekend after a disastrous start to the season which has seen a run of losses and a five game winless streak.

He was replaced by former Reds coach John Kosmina - but with three years remaining on his four year contract, Coolen was given charge of the youth department.

However Coolen appears to have rejected his new role and taken the first steps towards suing the club.

A spokesman added: "Adelaide United FC rejects that there is any grievance upon which Football Federation Australia could adjudicate upon."