To see Mrdja train with his team-mates today...

The Mrdja deal has come under fire from all quarters after it was simultaneously announced the Mariners had terminated his contract to allow him to sign for Melbourne Victory...but return to the Mariners on a new contract next season.

Mrdja joined Victory outside the transfer window as an injury replacement player for Billy Celeski to compete in the A-League finals series and Melbourne's Asian Champions League campaign.

He will then rejoin Central Coast for the new A-League season in August.

Rival clubs and commentators have all said the deal appears to effectively be a loan which would be outlawed outside the transfer window which closed in January.

But today the FFA confessed they had been kept in the dark about Mrdja's contracted return to the Mariners at the end of the spell with Victory.

And the admission throws new doubt on the validity of the move.

Additionally, while Mrdja's move appears to technically be within the rules, the FFA were in a position to reject it on the grounds that it threatened to jeopardise the integrity of the A-League.

Article 6.1 of FIFA transfer regulations states:

"Players may only be registered during one of the two annual registration periods fixed by the relevant association. As an exception to this rule, a professional whose contract has expired prior to the end of a registration period may be registered outside that registration period.

"Associations are authorised to register such professionals provided due consideration is given to the sporting integrity of the relevant competition. Where a contract has been terminated with just cause, FIFA may take provisional measures in order to avoid abuse."

There has been an established precedent for late season signings in the A-League close to the finals series.

But the fact that Mrdja is contracted to return to the Mariners at the end of his Victory spell as a result of contrived contract terminations and re-signings is what makes the Mrdja deal unique.

However as the FFA say they were unaware of his new deal with the Mariners, they were not in a position to see that  it was unprecedented, and effectively a loan outside the transfer window.

But at the time Mrdja's move to Victory was revealed last week, a Central Coast Mariners' press release said his switch south was a contracted part of his new deal.

The FFA still can revisit the decision under Article 8 of FIFA's transfer regulations.

It states: "The application for registration of a professional must be submitted together with a copy of the player's contract.

"The relevant decisionmaking body has discretion to take account of any contractual amendments or additional agreements that have not been duly submitted to it."

Today though the FFA insisted the deal would stand and said they would be saying no more on the subject until the rules are reviewed at the end of the season.

They admitted they only found out about Mrdja's new deal with the Mariners after they had approved his Victory switch. At that point they believed the deal was a straightforward contract termination and injury replacement.

They added: "The FFA considered the regulation and the deal was legitimate under the regulation that has been there since day one and used on dozens of occasions by a range of clubs to replace injured players.

"That was its purpose and it will be under review at the end of the season. We will review the rule. [We are] not going into any more detail."

Melbourne Victory also confirmed they still intended to register Mrdja as part of their Asian Champions League squad when it's finalised next week.

Mrdja today defended his move, and relished that he may earn a place in history if the rules that allowed it are overturned next season.

"That's always a positive too, my name is always going to be there, the guy who did it," he said. "It was all legal, both parties were happy, it's gone through and I'm happy about it."

But Sydney FC vice-chairman Scott Barlow today joined the row, adding: "The early termination of his contract clearly had nothing to do with the player leaving the club.

"It was purposely done in order to put the player in a position to temporarily join a new club, creating what is effectively a loan deal.

"Approval of these kinds of player movements at such a critical stage of the season seriously undermines the credibility of the A-League."

And Newcastle Jets coach Branko Culina also told the Sydney Morning Herald: "I know the rules are there and clubs aren't breaking anything as it currently stands but there's no question this needs to be looked at by the FFA.

"'I don't think there's anywhere else around the world where you would be allowed to do this."

To see Mrdja train with his team-mates today...