Ndombele, who had been coming into form for Spurs, came off at half-time of the 1-1 draw with Sheffield United after an apparent groin injury. He suffered it in the first half, but wanted to play on until the physio told Pochettino otherwise at half-time.
Spurs were again not at their best as Son Heung-min’s goal was cancelled out by George Baldock’s late effort.
“We need to assess him,” Pochettino said. “I don’t know anything at this moment. He felt pain in his groin but I don’t know if that was before or during the game it happened. Yes, a strange situation because my feeling was that he wasn’t comfortable on the pitch but he said he was OK during the game.
“Then in the end we arrived at half-time and the doctor said to me that we needed to change because he can’t continue in the game. That type of situation sometimes affects the team.
“It’s not an excuse only to explain that when you play against a team like Sheffield United, 11 players focused with full energy, if you drop a little bit someone for different reasons, you’re going to struggle.
“We struggled from the beginning. I felt in the last 15 minutes in the second half we grew on the pitch and started to dominate and play better, but of course from the beginning we suffered a lot.”
While Spurs are having a miserable time in the league, Sheffield United could not be having more fun on their return to the Premier League and they occupy the top six.
They remain unbeaten away from home, but Chris Wilder – who saw his side have a goal marginally ruled out for offside by VAR – was left wanting more.
He said: “The position that we were in coming here, we have got 16 points from 11 games, can those boys afford to have a day off? People will say that Tottenham were favourites to win, I get that, there is no disgrace in getting beat here.
“Sixteen points looks alright after today, but are we happy with that? I asked them that before the game and to a man they said they are not. I think they are a little bit disappointed we didn’t move from 16 points to 19.”
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