Tottenham are concerned Harry Kane could angle for a summer exit away from the club.
Kane's frustrations have come to the boil after a string of disappointing results in all competitions to begin the campaign.
Spurs have been beaten by Leicester and Newcastle already in the Premier League as well as a humiliating exit to League Two Colchester in the Carabao Cup.
They squandered a two-goal lead to draw their opening Champions League match at Olympiakos before further embarrassment as they shipped seven at home for the first time in their history against Bayern Munich on Tuesday.
And that has led to the club fearing he is losing patience in north London, report The Times.
Kane's future could also come into sharper focus if Mauricio Pochettino leaves the club with the Argentine continuously linked with Real Madrid and Manchester United.