The 21-year-old has been chased by Mauricio Pochettino all summer, and he has now completed a club-record deal in the region of £40million.
Alongside the quality of Toby Alderweireld and the guile of Jan Vertonghen (a pair of ex-Ajax stars themselves), Sanchez will blossom into a fine player, well worth the £42m Tottenham are reportedly shelling out.
Pochettino said: "I want four players".
Sanchez joined Ajax from Colombian club Atletico Nacional in 2016 for £3.8m and played for the Dutch side in their Europa League final defeat by Manchester United in May.
Paulo Gazzaniga's last Premier League outing was a 2-0 home defeat to Spurs
'I am very excited to be signing for such a famous club as Tottenham Hotspur. I can not speak about that rumour. Not only our fans, we expect to sign some players before the end of the transfer window.
Spurs have endured a frustrating time in the transfer market so far this summer, but with Pochettino demanding at least four new signings, are now pressing the accelerator. If they follow through, that would be three more in just under two weeks.
Sanchez's arrival is set to spell the end of Kevin Wimmer's career at Spurs, with West Bromwich Albion favourites to land the Austrian global.
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