In May Alexis Sánchez released his autobiographical movie in Chile. It is titled Mi Amigo Alexis – My Friend Alexis – and shows his beginnings as an always smiling kid kicking a ball in a dirt field in his hometown Tocopilla, in the north of Chile. It was like the Joker had drawn a forever-lasting smile on his face.

Where did that joyful and happy boy go? That’s the question every fan in Chile has been asking since the forward joined Manchester United in January 2018.

After a splendid spell at Arsenal, where he was given the freedom to do what he wanted with the ball at his feet, Sánchez suffered a new experience with United. He went to compete for championships and win trophies but ended up losing his true essence.

Sánchez was grounded first by José Mourinho and then by Ole Gunnar Solskjær. He was asked to do more dirty work, such as tracking defenders, or deployed on the wings. But he didn’t seem to enjoy those tasks if not allowed to express himself in his natural playful ways.

Sánchez made his debut for Cobreloa as a 16-year-old and was forced to grow up in a hurry. This might have hidden his childish personality, one that needed nurture and love. Maybe that’s why he is so fond of his dogs, Atom and Humber: animals don’t know about adult life troubles and always receive you at the front door with their tongues out.

Pep Guardiola knew that well. Years ago, as Barcelona manager, he took Sánchez to task after the player got injured in the last minute of a match, like a father calling out a son who had broken something in the house. But Guardiola also knew how to speak to Sánchez’s childish soul and make him feel loved and secure.

Alexis Sánchez in Milan on Wednesday for his medical. Photograph: Maurizio Maule/Rex/Shutterstock

“The Wonder Kid”, as he is called in Chile despite being 30 years old, came from a poor environment and did everything he could to give his family a better life. That’s the best example of how he responds to big challenges. He didn’t even flinch when scoring a Panenka penalty against Argentina to win the 2015 Copa América final in a shootout. He doesn’t know pressure when he is on the ball; he just plays like he did on the dirt field of Tocopilla.

Things can’t go worse in Italy than they did in Manchester. He will have South American teammates at Internazionale to help him settle (though he had these at United too) and a coach, Antonio Conte, who always wanted him. Now it’s up to Sánchez to find that smiling kid hidden somewhere inside himself.

Samuel Ferreiro is a journalist with the Chilean newspaper Las Ultimas Noticias