Merson says he worries about Tottenham star Kane ahead of England clash

England's midfielder Dele Alli (top L) celebrates with England's forward Harry Kane (3rdR) and teammates after scoring their second goal during the Russia 2018 World Cup quarter-final...

England are two games away from winning the World Cup, but Paul Merson reckons Kane and Alli are yet to peak.

TOPSHOT - England's midfielder Dele Alli (C) celebrates with England's forward Harry Kane after scoring their second goal during the Russia 2018 World Cup quarter-final football match...

England face Croatia on Wednesday in the semifinal of the World Cup, and a tough battle is underway given the quality of both teams.

The Three Lions have been in fine form in Russia, breaking their penalty shootout curse and playing well despite their lack of tournament experience.

Tottenham striker Harry Kane has six goals to his name, while his Spurs teammate Dele Alli finally opened his World Cup account with a fine header that sealed the victory in the quarterfinals against Sweden.

The duo have been instrumental to manager Gareth Southgate's plans thus far, but former Arsenal star and pundit Paul Merson believes they haven't reached their peak at the tournament yet.

He reckons Kane is tired and in bad need of a rest ahead of the semis, while Alli isn't fully fit and hasn’t been playing well.

"I’m slightly worried about Harry Kane. He looks tired. I saw him look up and pass the ball off at the end of the Sweden game when he could have had a shot," Merson wrote in his Daily Star column.

"A fully firing Harry Kane takes a shot there. I think that showed he is mentally tired. He needs to rest before the semi. He’s scored loads of goals but hasn’t been a 9/10 in any of the games yet."

Despite Alli's lack of top form, Merson believes finally scoring would surely have boosted the confidence of the Tottenham star, and the fact that he still has the knack of being in the right place at the right time should be a massive plus for England going forward in the tournament.

Tottenham Hotspur's English midfielder Dele Alli (R) celebrates scoring the opening goal with Tottenham Hotspur's English striker Harry Kane during the English Premier League football...

The Three Lions last reached the semifinals of the World Cup in 1990, and have surely surpassed expectations by going this far in Russia.

Going all the way to the final will definitely give the players massive self-confidence as far as their chances of returning home with the prize goes.

Kane and Alli hitting top form for the clash against the Croats will come very handy for the team, as the Spurs duo are unplayable on their day.

And they can't afford to let their selves and the team down at such a crucial stage.

Harry Kane of Tottenham Hotspur celebrates with Dele Alli of Tottenham Hotspur after scoring his sides first goal during the Premier League match between Tottenham Hotspur and Newcastle...

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