At 32-years-old, Vertonghen is still a very important player for Pochettino. In the current season he has already played 500 minutes, that have been shared between 5 games.
The Belgian player's contract runs out on the 30th June 2020 and there are several clubs interested in him because he always has good performances and he would arrive as a free agent at the end of the season.
Tottenham were leaning towards his exit, but, in the last couple of days, it seems that they are looking at the opposite. According to the portal 'TMW', the Belgian could renew.
The English club's director will try to see the viability of a contract extension, after consulting with the coaching staff, this would mean that the ball is entirely in Vertonghen's court.