The England captain was injured after being caught in the middle of Phil Jones and Victor Lindelof as Spurs chased an equaliser against United.

He received treatment after the full-time whistle before walking off the Wembley pitch extremely gingerly.

Kane did not emerge through the mixed zone after full-time as he was selected for a post-match doping test, so it was unclear how heavily he was walking or whether he had a foot brace on or needed crutches.

Any lengthy absence for Kane would leave Spurs short of attacking options ahead of an important part of the season, with Son Heung-min away on international duty, Lucas Moura still injured himself and Fernando Llorente and Vincent Janssen expected to leave the club this month.

Defender Jan Vertonghen is backing his team-mates to cover the potential absence of Kane and Son.

"We have to assess the other cases as well but these two guys are just massive for us," he said.

"Especially over the last couple of months, they've been immense. We've got other great players.

"They're also vital for us but we hope they'll both be back soon."

Kane's possible spell out compounds what has been an extraordinary season of injuries for Spurs.

Vertonghen, who himself has missed 17 games with two separate injuries, says it is "crazy" how Spurs have been able to challenge for the Premier League title up until Sunday's damaging defeat.

"(They were bad) especially at the beginning of the season," Vertonghen said. "In the last couple of weeks it was OK.

"But it's a shame, obviously. It's one of those things but that's why we have the other guys, the other guys have to stand up now.

"It's crazy. But you always have to think with the players you've got.

"I'm sure other teams have had injuries but we've had a couple more.

"I think you've always seen that every time someone got injured, other people were there to perform. I hope we'll see that this time."

Meanwhile, Tottenham are investigating a reported incident of racist abuse against Son during the defeat to Manchester United.

A season-ticket holder has been in contact with the club after witnessing the alleged abuse, accusing stewards of not intervening and then claiming to be abused by the perpetrator.

Spurs, who say they take all allegations seriously, will work with the supporter to investigate.

A Tottenham supporter was recently handed a four-year banning order after throwing a banana skin at Arsenal striker Pierre-Emerick Aubameyang.

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