Tottenham manager Mauricio Pochettino has praised Dele Alli's "amazing character" but says "he still makes a lot of mistakes".
Alli scored the first goal in Tottenham's 3-1 win over Chelsea at Wembley on Saturday which took Spurs above the Blues to third in the Premier League.
The 22-year-old played a key role in Spurs' win which ended their London rivals' unbeaten start to the campaign and he later praised Pochettino's "amazing" tactics.
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In turn, Pochettino hailed Alli's return to top form but insisted there is still room for improvement.
"He is such a talented player and amazing character," said Pochettino.
"Sometimes he has done badly for himself. Sometimes you need to control the character. He's still so young and he needs control and we are here to help him.
"He makes a lot of mistakes still but we are here helping by being nice but strong, too.
"We want to help him with his career. We want to give him a really strong base and foundation to go on even higher.
"He made a massive impact when he joined us two-and-a-half years ago. It is never easy for a young guy to be consistent when so many things happen - and many things have happened because he is so young."
Tottenham now turn their attention to Wednesday's Champions League match against Inter Milan on Wednesday before facing Arsenal at the Emirates Stadium next Sunday live on Sky Sports.
With such a busy schedule Pochettino is planning to make changes to the line-up in the coming weeks.
"We're going to rotate the starting XI," the Spurs added. "We have ahead 11 games in less than 40 days before January. We're going to need all the squad fit to compete to play."