Emiliano Sala reportedly signed an invalid contract with Cardiff City just days before his and pilot David Ibbotson's tragic deaths in a plane crash over the English Channel.

As per the Telegraph, lawyers working on behalf of the Premier League have contacted the Bluebirds to inform them that the Argentine was not fully registered to play in the competition last month.

It is the latest twist in the row between Cardiff and Ligue 1 side Nantes over the £15m transfer fee for Sala.

The Telegraph report that Sala's contract with Cardiff was not compliant with Premier League rules and it was returned to the club for him to sign an amended version.

Cardiff are now planning to use his registration status in the English top-flight to argue that he was not their player when he sadly passed away.

The Welsh side have also asked Nantes to prove that the de-registration process from the French top-flight also went through correctly prior to the plane crash.

Nantes had threatened to pursue legal action over the payment from Cardiff, but are yet to act on any of their threats.

The first of three instalments for Sala's transfer fee was set to be paid today, but as we wrote earlier, that has now been delayed until at least February 27.

While the rows behind-the-scenes appear to be growing uglier, the response from Cardiff, Nantes and the rest of the footballing world on the pitches has been nothing short of exceptional.

Bluebirds boss Neil Warnock attended Sala's funeral in Argentina and the tribute from fans and players from the Welsh club has been perfect.

The only hope now is that the ugly legal rows going on are settled in the easiest, quickest and most respectful manner.

The world is also praying for Ibbotson's body to be found, with a search for the pilot set to be resumed shortly.