By Tottenham correspondent Tony Hughes

Mousa Dembele is not expected to be fit for Tottenham’s Europa League clash with Fiorentina, Football Insider sources understand.

The midfielder injured his groin during Spurs’ 1-0 FA Cup defeat by Crystal Palace on Sunday and was substituted at half-time.

Although the damage is not thought to be severe, a Tottenham source has told Football Insider that Dembele is struggling to be fit for the last-32 second leg match against Fiorentina and the Premier League match against Swansea three days later.

The Belgium international has been one of the London club’s outstanding players this season and is regarded as a key man in their bid to win the Premier League title.

Manager Mauricio Pochettino revealed on Sunday that Dembele was suffering from a groin injury as he admitted the London club’s gruelling fixture list was taking its toll.

“Mousa Dembele had a smaller groin problem,” Pochettino said at his media conference. “That’s why we changed him at half-time.

High flyers: Pochettino's team are second in the Premier League

High flyers: Pochettino’s team are second in the Premier League

“It’s a tough period for us. We have a crazy schedule but now we need to look forward to be ready for next Thursday.”

In other Tottenham injury news, Erik Lamela should return to face Fiorentina after missing two matches through illness.