Tottenham assistant manager Cristian Stellini issued an apology after their FA Cup exit (PA)

Tottenham assistant coach Cristian Stellini issued an apology to supporters following their FA Cup fifth-round defeat to Sheffield United on Wednesday evening.

Spurs delivered a poor display against their Championship opponents as Iliman Ndiaye’s close range effort in the second half was enough to secure the upset at Bramall Lane.

‘We used a good team to play this game against this type of opponent, the problem was the energy,’ Stellini said after Spurs’ FA Cup exit.

‘If that’s not at the same level as your opponent sometimes you can lose. We had opportunities but couldn’t find the target. This was the problem for me, the energy in this type of game. I’m disappointed with that.

‘It’s not about motivation, I don’t think so. If you don’t play consistently, maybe sometimes you try to manage the energy differently or drop it in the start because you think the game is easy. Our games are never easy. It’s about mentality.

Iliman Ndiaye scored Sheffield United’s winner to dump Spurs out of the FA Cup (Reuters)

‘I think we missed a big opportunity. We have to apologise to the fans, there were 5,000 here to watch our performance and we apologise because we missed a great opportunity.’

Stellini, who continues to stand in for Antonio Conte following the Italian’s gallbladder surgery, also defended the decision to start Harry Kane as a substitute.

‘It is not a regret,’ Stellini said.

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‘We need to look in the medium period, we have many games.

‘Harry Kane played in the last six games, one time with fever, one time with a problem. We have to take care of our best player.

‘It’s not about Harry because we played with Richarlison, Lucas Moura and Sonny. I think it is good enough to play in this competition and against this sort of team.’

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Spurs were beaten 1-0 by Sheffield United.