Barcelona superstar Neymar's troubles with the Spanish authorities continued when a fraud case against the player and his father was reopened on Friday following a successful appeal by Spanish prosecutors, a court filing showed.

In July a judge ruled that irregularities in the Brazilian's 2013 transfer to Barcelona were detected, but said it was an issue for a civil court, not a criminal court to settle.

However, prosecutors successfully argued the player and his father were aware of potentially fraudulent dealings between Barcelona and his former club Santos to the detriment of DIS, a Brazilian investment company who owned 40 percent of the player's sporting rights at the time of the transfer.

Spain's National Court "fully overturned" Judge Jose de la Mata's decision two months ago, allowing the case to proceed.

The decision is another blow to the image of the Spanish champions and Neymar, who had hoped to bring an end to the murky affair when the club agreed to pay a 5.5-million-euro ($6.2 million) fine in a deal with prosecutors in June to settle a separate case and ensure the club avoided trial on tax-evasion charges over the transfer.

"FC Barcelona expresses its disagreement with the reasoning included in this decision," the club said in a statement.

"The investigating judge, who initially had agreed to dismiss the case against all those investigated, must now reopen the case and end up holding a trial.

"In the trial FC Barcelona will maintain the version of events it has always defended throughout the process and prove the innocence of all those investigated."

Neymar, 24, his father (also Neymar), Barcelona president Josep Maria Bartomeu and his predecessor Sandro Rosell were all called to testify in the case in February.

Barcelona originally published the fee in the transfer as 57.1 million euros, with 40 million euros of that given to the player's family.

But Spanish authorities believe the true transfer figure was at least 83 million euros because of a series of extra agreements tied to the transfer between the two clubs.

Santos received just 17.1 million, 6.8 million euros of which went to DIS.

DIS has claimed it was cheated of its real share firstly because part of the transfer fee was concealed by Barcelona and Santos.

Moreover, DIS also believes a pre-contract agreement between Neymar and Barca impeded other clubs from making offers for the player, affecting the value of the transfer fee.

Accustomed to upheaval

Neymar is far from the only Barca star to find himself embroiled in problems with the Spanish authorities.

Five-time World Player of the Year Lionel Messi and his father were given 21-month jail sentences in July for tax fraud relating to the player's image rights.

Messi is appealing the verdict, but the prison sentences are likely to be suspended as is common in Spain for first offences for non-violent crimes carrying a sentence of less than two years.

"If there is one player used to dealing with different situations and one team used to dealing with different situations, it is Barcelona," said Barca coach Luis Enrique on Friday.

"All the players and their coach are used to dealing with things that have nothing to do with football."

Barca's Argentine defender Javier Mascherano also agreed a one-year suspended sentence with authorities for tax fraud earlier this year.

The off-field upheaval hasn't affected Barca or Neymar with the signing an undoubted sporting success as he has formed one of the most fearsome strike partnerships of all-time with Messi and Luis Suarez.

Barca have won back-to-back Spanish league and Cup doubles with the trio and the Champions League in 2015.

Neymar signed a bumper new deal with the club to extend his contract until 2021 in July despite admitting last week he held talks with Paris Saint-Germain amidst interest from a host of top European clubs in luring him away.

And he also handled the pressure of being Brazil's poster boy for the Rio Olympics by delivering the hosts' first ever football gold medal with a goal and winning penalty in the final against Germany last month.