Dele Alli has been hailed by Mauricio Pochettino ahead of Newcastle United's visit to White Hart Lane.
The Tottenham Hotspur midfielder scored his fourth goal of the season in Saturday's 1-1 draw against West Bromwich Albion.
Newcastle were close to signing Alli for around £4million in January, but the 19-year-old ended up joining the north London club in a reported £5million deal.
Alli, capped by England at senior level this season, will face United on Sunday when United visit White Hart Lane.
And Tottenham head coach Pochettino said: "He has unbelievable potential. He is very young, and every game he shows his quality.
"For me 19, 18, 17 or 30 is the same. It's not about age, it's about performance and desire. It's not about age or names."
Meanwhile, fifth-placed Tottenham are unbeaten in 14 Premier League games, while Newcastle beat Liverpool 2-0 at the weekend to move up one place to 18th.
Pochettino, speaking ahead of Thursday's Europa League visit of Monaco, played down the significance of what is a club record.
"We don't think too much on that," said Pochettino. "We want to win every game, our idea is to win the next three points against Newcastle.
"It's very important for our mentality that after 15 games of the season we are 14 games unbeaten."