The number has become synonymous with Silva at both Club and international level, winning four Premier League titles, two FA Cups and four League Cups during a nine-year spell wearing the 21 shirt at City, as well as two European Championships and a World Cup for Spain.
And in an outtake from the new Silva documentary Made in Gran Canaria, available to watch on City+, the mercurial midfielder says it came from an opportune moment of deception.
“I moved to Eibar a very short time before the beginning of the 2004-05 season and it was the only one available,” Silva says. “It was given to me.
“Then I moved to Celta on loan and 21 was already taken, so I took the number 16.
“Afterwards, I went back to Valencia and 19 and 21 were the only numbers left.
“I was wearing the 21 before and it was also the one of Pablo Aimar at Valencia, a player which, in terms of playing style, was the most similar to me, so I wanted it for myself.
“And here’s an anecdote I never told to Jaime Gavilán. That year when both of us arrived there, 19 and 21 were the only squad numbers available, and I got on really well with Curro Torres.
“Me and Gavilán, both newcomers, held a raffle and in a moment when he was distracted, Curro told me which one to pick. It was hidden in his hands and I picked the one with the 21.
“We cheated a little bit there… and Gavi was never aware of that.
“And I’ve been wearing the 21 shirt until now… and I never told him! I hope he will understand…”
Silva says his love of the No. 21 shirt was ignited by watching his idols Juan Carlos Valeron and Michael Laudrup.
Like Silva, Valeron was born in Arguineguín, a small town on the South Coast on Gran Canaria, and possessed outstanding technical quality.
He went on to have a top-level career in La Liga with Mallorca, Atletico Madrid and Deportivo la Coruna, as well as winning 46 caps for Spain.
And Laudrup, a European Cup winner with Barcelona who also won five La Liga titles during a distinguished playing career, was one of the finest dribblers the game has ever seen, something that inspired a young Silva.
“Juan Carlos Valerón and his brother Miguel Ángel, both played with my dad here in Arguineguín,” Silva says.
“Juan Carlos was always a role model to me. I knew him and he was an incredible person.
“And then it was Laudrup. I’ve always said that he was my childhood idol.
“Both were a really good reference for me.”
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