Arsenal missed out on signing Cristiano Ronaldo as a teenager due to financial constraints, according to former Gunners scout Damien Comolli.
The Portugal international is understood to have attracted interest from north London during his early days at Sporting Lisbon and even visited Arsenal's London Colney training ground.
However, the Gunners were unable to reach an agreement to bring Ronaldo to Highbury, opening the door for Manchester United to sign him in 2003.
"The first time I saw Ronaldo, it was at the Montaigu tournament, he was 15," former Tottenham and Liverpool director of football Comolli told French TV station SFR Sport.
"He played against Japan before and I thought: 'Who the hell is this?'
"At half-time, I called my contact in Portugal to which I said that I had seen a phenomenon. Since Thierry Henry, I had never seen anyone like that.
"He came to the [Arsenal] training centre twice. Nobody knows that. He met Thierry, who was his idol. But when it came to making the transfer, there was no money.
"Some months later, Manchester United secured a partnership with Sporting and they played a friendly match in Lisbon. He slaughtered them and Sir Alex Ferguson said: 'He must go to United'."
Ronaldo won nine major honours during his time at Old Trafford before being moving to Madrid for a then world-record £80m fee in 2009.
He has since gone on to become one of the world's greatest footballers, winning 18 major honours at club and international level as well as the Ballon d'Or on three occasions.
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