Tottenham Hotspur are reportedly growing increasingly worried about the possibility of losing Toby Alderweireld on a free transfer.

The future of the defender has been well-documented as a result of a £25m release clause which came into effect earlier in the summer window.

However, few clubs expressed an interest in exercising that option, while there has seemingly been no progress with regards to the centre-back penning an extended deal.

According to The Mirror, Spurs now fear that the 30-year-old will walk away for nothing at the end of the campaign.

While Alderweireld remains first choice under Mauricio Pochettino, that option may prove attractive given that his next contract could be the last long-term deal of his career.

Spurs face a similar dilemma with playmaker Christian Eriksen, who has also failed to secure a transfer to another club this summer.