Mauricio Pochettino has confirmed Mousa Dembele has been sidelined with an ankle problem.
The Belgium international, who underwent foot surgery in May, played 79 minutes of Tottenham's EFL Cup win over Barnsley on Tuesday before being withdrawn for Eric Dier.
Dembele has made three starts in the Premier League for Spurs this season, but was left out of Pochettino's squad to face West Ham on Saturday.
And the Spurs boss has revealed the 30-year-old suffered another injury against Barnsley.
Speaking at the London Stadium ahead of the game, Pochettino said: "After the cup game he started to feel a problem with his ankle. We hope it’s not a big issue."
After coming through surgery at the end of last season, Dembele conceded that he would never "play at 100 per cent" given his ongoing struggles with various injuries.
At the time Dembele vowed to play though the pain, but the midfielder will not be risked against West Ham following his latest knock.
In Pictures | West Ham vs Tottenham | 23/09/2017
It's another major blow for Pochettino, whose midfield has already been weakened by the loss of Victor Wanyama to injury earlier this season.
The Kenyan has not played since the defeat to Chelsea at Wembley and is not due back until at least October.
