Tottenham have been linked with a move for Ajax defender.
Sanchez, 21, is a Colombia international who played a key role for the Dutch club last season.
Former Tottenham defender Graham Roberts said he feels Sanchez would be an excellent signing for the club.
Would love this guy to come what's incredible last Season and final https://t.co/iARqLbYPEW— Graham Roberts (@GrahamRoberts4) August 9, 2017
Sanchez made 32 Eredivisie appearances for Ajax last season, scoring six times.
He also was a regular as his side reached the Europa League final, before being defeated by Manchester United.
Sanchez would link up with former Ajax defenders Toby Alderweireld and Jan Vertonghen at Spurs, and potentially form a formidable three man backline.
Spurs need further options at the back and Sanchez would give them greater flexibility if they can get a deal done.