After 10 years of incredible service, the Argentine called time on his Manchester City career and made the switch to Spanish giants, FC Barcelona.
It's been heavily reported that Sergio Agüero did in fact want to remain in Manchester, and his father has claimed that his hand was forced.
"My son was waiting right up to the last moment to renew with Man City but it didn’t happen. He is happy right now after signing for Barcelona. I see him happy. He didn’t know what was going to happen with his future."
"There were several clubs interested in signing him. Arsenal were interested and Chelsea to the last minute. If he didn’t stay in England, it was going to be Italy or Spain."
“He’s been friends with Lionel Messi since they were 15 and they’ve always talked. It looks like Messi is going to stay at Barcelona so they’re going to play together,” Aguero's father admitted.
However, Castillo went on to further launch a scathing attack on the Manchester City manager, accusing him of wanting to be the 'protagonist'.
"I don't believe his tears," Castillo said.
"For me, he never wanted Kun. He always wants to be the main man. I don't believe [in] Guardiola. He never wanted it [the Champions League trophy], he wants to be the protagonist of all the teams."
"He says that he [Aguero] is irreplaceable and he does not have him in the squad. There are things about Guardiola, he's a great coach, but from one day to the next the players change you, the environment changes. You never know if you're a starter or not."
"There's someone who says if you're not here to stay and you have no choice but to change. He [Aguero] was [allowed to stay] until the last time [he renewed his contract] but it was not possible [this time] - a team where he is an idol."
For now, Sergio Aguero will be focused on international duty with Argentina, before then refocussing on Barcelona - where he will be aiming to secure the La Liga title in his first season under Lionel Messi and co.
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