PSG paid 222 million euros to trigger the buyout clause in the Brazil forward's Barcelona contract last August, making him the most expensive signing in soccer history.
Barcelona had believed Neymar was going to stay at the club, with Mestre stating he was 200 percent sure the Brazilian would be at the Nou Camp this season.
"What hurt me the most was the way it happened," Mestre told newspaper Diario Sport in an interview.
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"We were all on tour talking with him and his father, and they were not transparent.
"If he came to us and said, I want to go, like Cesc (Fabregas), Pedro, Alexis (Sanchez), and (Javier) Mascherano did, we would have reached an agreement. What you can't do is rock the boat.
"He played cat-and-mouse with us. It arrived at a point where we saw where things were going so we told him we would not pay his contract renewal loyalty fee."

Paris Saint-Germain's Brazilian forward Neymar

Image credit: Getty Images

Neymar and his representatives did not respond to a request for comment from Reuters.
Neymar renewed his deal with Barcelona in July 2016, which meant he was owed a 26-million-euros renewal bonus.
Barcelona did not pay it and deposited the money with a notary. FIFA, world soccer's governing body, are investigating an official complaint from the forward regarding the matter.
Mestre said Neymar's behaviour caused inflation in the transfer market.
"He told us nothing. If he had done PSG would have been able to buy him for less money and it would have cost us less to sign players too," added the Barcelona executive.
"What Neymar's behaviour created was the market inflation. We would have saved a lot of money and a lot of media noise."
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