The 21-year-old became the north London club's record transfer signing after he arrived from Ajax last summer in an initial €40m (£34.8m, $49.7m) deal with another €2m (£1.74, $2.5m) in add-ons.
Regarded as one of the brightest defensive talents in Europe, Sanchez drew interest from the likes of Chelsea and Bayern Munich during Ajax's run to the Europa League final last year.
Barcelona, who were also linked, seemed to be the favourites for the Colombian's signature though, as Sanchez revealed his ambition of playing for the Catalans last May.
"Obviously [I would like to play for Barcelona]," Sanchez had told Cadena Ser at the time. "It's a huge compliment [to be linked with them]. Who doesn't want to play in a club as big as Barcelona? Everyone wants to be part of a team like that as they are always one of the world's elite."
However, Sanchez would opt to join Tottenham instead, revealing upon his signing that he made his decision based on footballing rather than marketing reasons. The young defender has gone on to make 26 appearances in all competitions this season for Mauricio Pochettino's men.
It was not the first time that he had snubbed La Blaugrana. Before his move to Ajax, Sanchez had the opportunity to move to Barcelona in 2016 when he was still playing in his homeland for Atletico Nacional.
However, he turned them down at the time as well in favour of a move to Ajax as he was only given assurances of featuring for Barcelona B while he wanted first team football.
"It's true that I was always linked [with Barcelona in 2016]," he told MARCA Colombia. "There was an offer on the table, but you have to think about the conditions.
"I had just won the Libertadores and had to go to Barcelona's second team. Although I was sure that I would finish up in the first team, because I have a lot of confidence in me and my ability to achieve important things, I played 50 games at Ajax and [that was] what I needed."