The Catalan giant announced an €11.8million deal to bring Mina from Palmeiras on Friday (AEDT), the Colombia international putting pen to paper on a five-and-a-half-year contract.
The 23 year-old is pleased to join a club possessing top-tier talent, detailing the impact his first meeting with Messi and Luis Suarez had on him.
"For me, he [Messi] is the best in the world. The first impression I got of him was one of humility. I got goosebumps when Messi approached me with Suarez in the dressing room," said Mina.
The centre-back raised eyebrows by stepping onto the Camp Nou pitch with bare feet during his presentation to supporters.
"There is a saying in my country that says, 'Touch the land you want to conquer with the sole of your feet.' And here I want to make history with everyone. I always do it and I hope to succeed," Mina said.
"I have come to work. To contribute to the team and learn from my team-mates. This is a great club and since arriving you can feel the atmosphere here."
Mina will compete with Gerard Pique, Thomas Vermaelen, Samuel Umtiti and Javier Mascherano for a spot in the centre of Ernesto Valverde's defence.
It could represent a risk just five months before Colombia's participation in the World Cup, but the former Palmeiras man has no concerns about potentially missing out.
"I was given the opportunity to come now and I did not think twice. I'm going to work to bring something to the best players in the world," Mina said. "I'm calm. I came to work, to contribute, to be with the best. With the work that we will all do, I will fight to be at the World Cup.
"I have to go step by step. I have to do things well and fit well in the group."