Mauricio Pochettino told Dele Alli to "keep his feet on the grass" after the Tottenham midfielder shone against Aston Villa.
The newly-capped England teenager scored Spurs' second goal in a 3-1 win that stretched his side's unbeaten Premier League run to 10 matches.
Alli walked away with the Monday Night Football man-of-the-match award and a ringing endorsement from team-mate Jan Vertonghen, who called him "unbelievable" in the post-match interviews.
The Spurs manager was less effusive, telling Sky Sports: "We need to provide him with the tools to improve his game.
"He's young - I always repeat that the young players need to stay with their feet on the grass. This is very important, but when you have quality like he has, you need to push him, to put pressure and try to improve his game.
"But I'm very pleased with him and the whole team."
Spurs were cruising at 2-0, but Jordan Ayew's late goal at White Hart Lane led to a flurry of Villa chances before Harry Kane killed the game with a third in added time.
Pochettino said: "In football, you need to keep your focus on the game, and maybe because our mentality is always to go forward we lose our position on the pitch.
"We conceded a goal - it was our mistake - but that's football, and I'm happy and thinking about the next game."
Kane has now scored four times in two games after one in his previous 11 club games, and Pochettino said: "He's confident and trusting himself now again. We never doubted his quality."