Napkin used to sign 13-year-old Lionel Messi to go up for auction - with a starting price of £300,000

A napkin used to ensure a 13-year-old Lionel Messi signed for Barcelona is to be sold at auction - with a starting price of £300,000.

The napkin was written on in blue ballpoint ink by Barcelona coach Carles Rexach and served as the club's commitment to sign the Argentinian prodigy.

It would become a pivotal moment in the history of the club, with Messi going on to win dozens of trophies with the Spanish side - becoming arguably the greatest player in the history of the game in the process.

The 16.5 x 16.5 cm napkin is now being put up for auction on behalf of Horacio Gaggioli, the agent who brought Messi to the attention of Mr Rexach, and who was at the table when it was signed.

It will be put under the hammer in an online auction by Bonhams in March, with a starting price of £300,000.

An ultimatum

Messi had come to the attention of Barcelona's scouts as a 12-year-old while playing for his local club, Newell's Old Boys, in Rosario, Argentina.

In September 2000, Messi and his father, Jorge, were flown to Barcelona for trials, but negotiations stalled.

While Mr Rexach was convinced of Messi's talent, board members at the club had their doubts.

Firstly, Messi was diagnosed with a growth hormone deficiency as a child and would require expensive treatment, which his family were unable to afford.

Club bosses were also concerned at the prospect of bringing a player from Argentina to Spain at such a young age.

A fateful napkin

By December, Jorge, frustrated at the lack of movement, eventually made an ultimatum to the club - sign my son or lose him.

So the story goes that Mr Rexach, without a piece of paper to hand, reached for the napkin and scribbled down a note, committing the club to sign 13-year-old Messi.

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Written in Spanish, the note read: "In Barcelona, on 14 December 2000 and in the presence of Messrs Minguella and Horacio, Carles Rexach, FC Barcelona's sporting director, hereby agrees, under his responsibility and regardless of any dissenting opinions, to sign the player Lionel Messi, provided that we keep to the amounts agreed upon."

That night, the then president of FC Barcelona, Joan Gaspart, finally confirmed the agreement, this time on more substantial paper.

The rest, as they say, is history.

Messi would go on to become Barcelona's talisman, helping the Spanish side to 35 trophies throughout his career at the club.

He would also become the club's all-time leading scorer, an eight-time Ballon d'Or winner, and a World Cup winner with Argentina.

Ian Ehling, head of fine books and manuscripts at Bonhams New York, said: "This is one of the most thrilling items I have ever handled. Yes, it's a paper napkin, but it's the famous napkin that was at the inception of Lionel Messi's career.

"It changed the life of Messi, the future of FC Barcelona, and was instrumental in giving some of the most glorious moments of football to billions of fans around the globe."

Messi's napkin is one of the most famous in history, alongside one drawn upon by Pablo Picasso in lieu of payment for a meal in 1945, and another featuring a red lipstick kiss from Marilyn Monroe from 1962.