Madrid - Neymar admitted that he chose to leave Barcelona for Paris Saint-Germain against the advice of his father on Friday, just before arriving in the French capital.
"A sportsman needs challenges. And for the second time in my life, I am going against the advice of my Dad," the Brazilian wrote in a long post in Spanish on his Instagram account on Thursday night.
"Dad, I understand and respect your opinion, but my decision is taken, I ask that you support me as you always have done," he added.
Neymar signed a five-year deal with PSG, in which he is expected to earn €30 million net per year, on Thursday.
He earlier severed his ties with Barcelona after paying the colossal sum of €222 million to buyout his contract.
That means the transfer is a new world record deal, more than double the previous record of 105 million euros paid by Manchester United to Juventus for Paul Pogba last year.
Neymar added that his family "has suffered a lot with problems that have occurred in this period of my career and deserve peace. It is a difficult decision, but one taken with the maturity of my 25 years."
The player's assurances could be seen as a way of hitting back at critics furious at his departure from Barcelona.
Catalan sports daily Sport on Thursday described the player's entourage as "toxic", blaming them for Neymar's departure.
Sport wrote of "the fatal intersection of two diabolical factors: the money of Qatar (which owns PSG via QSI, their sovereign wealth fund) and the monetary and sporting ambition of the Neymars."
Neymar's father is extremely close to his son, supervising his career and the negotiation of his contracts.
He has become a celebrity in his own right, even appearing in an advert alongside his son, who had insisted upon arriving at Barcelona that his shirt should carry the name "Neymar Jr".
Father and son are set to go on trial in Spain following an investigation into the player's transfer to Barcelona from Brazilian side Santos in 2013.
"I have accepted the offer from PSG to try to help the club win the titles the fans want. They presented to me an audacious career plan and I think I am ready for it," added Neymar on Instagram.
Of his four years at the Camp Nou, he added: "I have won everything a sportsman can win. I have experienced unforgettable moments."