Callum Hudson-Odoi says Maurizio Sarri told him to be "the best you can be" after handing him his first Premier League start in Chelsea's 3-0 win over Brighton.
The 18-year-old impressed as Chelsea eased to victory at Stamford Bridge.
He set up the opening goal for Olivier Giroud with a low cross and went close to scoring when he headed at Mat Ryan from close range.
"I am very happy with the win," he said. "We all did well, we worked very hard from the start and the mentality was good from the start. We had to get some rhythm after Cardiff [2-1 win on Sunday] and we bounced back very well."
Asked about Chelsea head coach Sarri's pre-match message, Hudson-Odoi added: "He just told me before the game to go and express yourself, be the best you can be. I feel comfortable and when you go through the game you get more and confident to get the ball and hopefully I did well!
"I can't say if I should or shouldn't start, I just have to keep working hard in training and hopefully the opportunities will come to get the starts as well."
Fellow Chelsea academy graduate Ruben Loftus-Cheek also started and caught the eye with a brilliant goal from outside the box.
"It's what we have both worked for all our lives," he said. "Years of hard work to come through the academy and get the opportunity to start a Premier League game together is good for the academy and us personally."
The win sees Chelsea maintain their top-four challenge as they move up to fifth in the Premier League table.
Loftus-Cheek added: "It's a massive three points and we will look to build on that with six points in our last two games and close the gap."