Pep Guardiola was left dazzled by the performance of young midfielder Jude Bellingham during Manchester City's Champions League quarter-final victory over Dortmund.
After impressing in the first leg of the tie Bellingham shone again in the return, and put his Dortmund side 1-0 up in Germany with a superb finish in the first half.
City eventually came back to win 2-1 on the night and 4-2 on aggregate, but England international Bellingham clearly made a big impression on Guardiola.
Speaking to reporters after the game the City boss joked that he could not get over the fact that the player is still just 17-years-old - and also lifted the lid on a discussion he had with Dortmund manager Edin Terzic about him.
"I cannot believe it, maybe he's a liar!" Guardiola said. "He's so good for 17-years-old, he's a fantastic player.
"There was one moment when he didn't get the ball from central defenders, how he shouts and demands that ball to him at 17 means a lot.
"I spoke with his manager, Edin [Terzic], and he told me what you see in these two games is like every training session."
Bellingham was not the only young Englishman to shine on the night, with Phil Foden again putting in a superb display and scoring the crucial winner to all but kill the tie.
And Guardiola added on him: "You have the feeling that he is a guy who never hides, he always creates something.
"He scored two important goals, the second goal in the Etihad and today helped us to be in the semi-final.
"He grew up. In the quarter-final of the Champions League, he was the important player to go through to play against Paris St-Germain."
Both players certainly look to have exciting futures, and appear all but certain to be included in Gareth Southgate's England squad for this summer's European Championships.