Spurs snubbed the chance to sign Real Madrid superstar Marco Asensio in 2014, according to reports.
The Spanish sensation was recommended to Mauricio Pochettino by top scout Ramon Planes.
But Tottenham – who did not sign any players this summer – failed to follow up on the tip, say Mundo Deportivo.
That paved the way for the 22-year-old to commit to Real Madrid in the same year, where he has twice won the Champions League already.
Asensio signed a whopping six-year deal this summer after joining the Bernabeu side from Mallorca.
And his new contract is said to contain an eye-watering £442million release clause.
Barcelona were also looking at Asensio but failed to act.
Pochettino was in his first season at the club when Planes made the suggestion.
Coincidentally, Planes has now joined Barcelona as first team technical secretary to work alongside Eric Abidal.
Planes worked for Spurs during the 2014/15 season after previously working for Hospitalet and Racing Santander.
Meanwhile, Spurs have been told they must fork out £67m to land Ajax’s Frenkie De Jong.
Poch and Co have identified the highly-rated 21-year-old as the man who could be a key cog in their midfield.
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