The Dane's performance was overshadowed by Callum Hudson-Odoi and goalscorer Ruben Loftus-Cheek.
Sarri said, "I have to say another thing. We are talking about Callum and Ruben, but I was impressed by the performance of Christensen.
"I want to speak also about him. In the last period Christensen has played five or six matches really very well."
Asked if all three academy graduates can be the future of the club, Sarri was enthusiastic.
"I think so, and I hope so. They are at the moment very important players, but their potential is higher, so in the future they can become top players. For this team the future could be good."