Pep Guardiola refused to predict whether Kylian Mbappe can reach the stratospheric levels of Lionel Messi, but warned "nobody can sit at the same table as" the Barcelona star.
Guardiola's Manchester City were one of the victims of Mbappe's sensational breakthrough campaign at Monaco last season – the teenager scoring in each leg of a thrilling Champions League last-16 tie that the Ligue 1 club won on away goals following a 6-6 draw.
In all, Mbappe scored 26 goals in 44 games as Monaco beat Paris Saint-Germain to the Ligue 1 title and reached the semi-finals in Europe.
Mbappe has since swapped the principality for PSG, linking up with Messi's former colleague Neymar as the Parisians look to muscle in on the fight for continental dominance.
The France international scored on his PSG debut, and followed it up with a strike against Celtic in midweek, but Guardiola says such feats at a young age do not guarantee future success.
"Nobody can sit at the same table as Messi," Guardiola said.
"Maybe Mbappe, he's a top player, he will be an outstanding player, I'm pretty sure of that.
"But to equal what Messi has done in 10 or 12 years, or Cristiano [Ronaldo], for example, we have to wait.
"I appreciate Mbappe wouldn't like me to put more pressure on his shoulders.
"I think Messi has the numbers of 60/70 games every season, in the big games, always being there to score and assist, never injured, always plays every three days, never injured because he controls his body.
"That's why I don't think we help with hypothetical suitors for him, saying you are going to be the new guy. So, let Mbappe have the fantastic career he will have and after we'll see in the future."