* Club did nothing wrong in Neymar deal, Bartomeu says
* Coach Martino says he prefers to focus on football (Adds Martino quotes)
BARCELONA, Feb 21 (Reuters) - Barcelona president Josep Bartomeu has said the operation to bring Neymar to the Catalan capital was "completely legal" and reiterated the club's innocence of tax fraud in signing the Brazil international.
In the latest twist to a saga that prompted Bartomeu's predecessor, Sandro Rosell, to step down last month, a Madrid court on Thursday charged the Spanish champions with defrauding the tax authority.
The club was forced on the defensive after a member filed a complaint against Rosell alleging misappropriation of funds and when details of Neymar's move from Santos to Barca came to light the judge overseeing the case granted the public prosecutor's request to lay charges for tax fraud.
"We are very comfortable because the contract is completely normal," Bartomeu said in an interview with Spanish television broadcaster TVE late on Thursday.
"We took advice, ourselves, the player, Santos, and we did everything legally," he added.
"We now intend to explain the nature of the negotiation and what the contracts are and we will show that they are completely legal. Everything that was done was done correctly. We would do the same again."
Neymar's high-profile move to Barcelona in the close season was initially shrouded in mystery and it was unclear what exactly was paid to whom and when.
After Rosell stepped down, Barca admitted he had cost 86.2 million euros ($118 million), including payments to the player and his family, and not 57.1 million as they originally said.
The judge has requested Barca's tax records relating to the deal and had asked the tax authority to calculate the scale of any alleged fraud.
Local media reported the club should have paid 9.1 million euros more in tax than they did. It is unclear what punishment is likely to be handed down if Barca are deemed culpable.
In a separate development on Thursday the court accepted a complaint by a Spanish non-governmental organisation that fights corruption called "Clean Hands".
The complaint accuses Rosell, Bartomeu, who was closely involved in the transfer negotiations, and another Barca vice president, Javier Faus, as well as Neymar's father, of misappropriation of funds and document fraud.
"Seeing as we are very relaxed it doesn't matter if they (Clean Hands) file a complaint against us," Bartomeu told TVE.
"We will defend ourselves from a position of strength and we will go where we have to go. This will all end up being a mere anecdote."
Barca's legal woes do not appear to be affecting their results on the pitch.
They secured a 2-0 win away to English Premier League side Manchester City in Tuesday's Champions League last 16, first leg, are joint top of La Liga with 14 games left and are through to April's King's Cup final to face Real Madrid.
Coach Gerardo Martino said on Friday that he could obviously not ignore the situation but wanted to focus on matches.
"I am not surprised and it is not something I can ignore either," the Argentine, in his first season in charge at the Nou Camp, told a news conference previewing Saturday's La Liga game at Real Sociedad.
"I guess the players already know what it is all about. But it is not something I should talk about," he added.
"I prefer to focus on soccer. That is what gives us and Barca fans most satisfaction."
($1 = 0.7293 euros) (Additional reporting by Elena Gyldenkerne in Barcelona, writing by Iain Rogers, editing by Sudipto Ganguly and Toby Davis)