The Argentina international sealed a move to White Hart Lane after the north London club broke their transfer record to land the 21-year-old from Roma in a £30m deal.
Lamela has so far made five appearances for Spurs, making two assists, and Spurs legend Ardiles needs no convincing of his talent.
“Lamela needs a little more time to bed into Tottenham but he will prove to be a great purchase,” said Ardiles.
“He is not as powerful but he is more skilled than Bale.
“He has been nicknamed the ‘new Messi’ and that’s right – it’s a sign of how talented he is.”
Ardiles also expressed his approval for Tottenham’s transfer business over the summer.
Spurs spent in excess of £100m to bring in seven new players following the departure of Gareth Bale to Real Madrid.
“We need players who can create but also finish over the summer,” he continued.
“Spurs did that and we had a fantastic transfer window with players for the future.”
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