Barcelona offered more money than Madrid, the player would've earned more.
Vinicius Junior's agent Frederico Pena
Vinicius, 16, completed a £38million move from Brazilian side Flamengo to sign for Real last week.
He was heavily linked with a move to Barcelona before agreeing to join their bitter rivals with Neymar said to be a big influence on him moving to the Nou Camp.
But he opted to snub Barcelona and his admiration of Neymar in favour of Real because he preferred the project more at the Bernabeu.
"Barcelona offered more money than Madrid, the player would've earned more,” said his agent Frederico Pena to Brazilian outlet Globoesporte.
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"But we arrived at an agreement with Madrid because the player preferred their project more.
“Some people believe that he chose Madrid for money, but they are wrong.
"Vinicius only concentrated on the sporting aspect and Real Madrid's position in the negotiations was better in that regard."
Vinicius will officially join Real Madrid next summer as he will remain at Flamengo on loan until July 2019.
But his agent believes Real’s signings of young talent in the past were a factor in his decision.
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New Real Madrid signing Vinicius Junior was offered more money to sign for Barcelona – Agent
"Varane, Ramos, Casemiro, Asensio, Marcelo. They all arrived before the age of 22 and they're all very important players in the first team now,” he added.
“Barcelona sign players who already know the team plays, except in Neymar's case, so it is more difficult as can be seen with Arda."
On Vinicius playing for Real next season, the agent added: "Madrid can sign players like Mbappe.
“We've got to see the player's development this year and what Madrid will need next summer. Then we'll know when he goes there.
"Vinicius will go to Madrid with his whole family. Such a young lad will need to be surrounded by his own."