Thomas Tuchel singled out N'Golo Kante for his impact in Chelsea's 3-0 win against Tottenham on Sunday.
The France international came off the bench to replace Mason Mount for the second half of the clash and helped the Blues recover from an underwhelming first 45 minutes.
Kante scored his side's second goal of the game and impressed the German coach with his overall performance.
What has been said?
"He played a huge part. N'Golo is N'Golo, he's unique, one of a kind and having him on the pitch makes such a huge difference to everything," Tuchel told BBC Match of the Day.
He added in a press conference: "He's a top player. If you have N'Golo, you have something everyone is looking for.
"He is a unqiue guy... He is fantastic."
Centre-back Thiago Silva also delighted the manager by popping up with the first goal, while Antonio Rudiger netted the third in stoppage time.
"It was nice that he almost scored twice. He was so strong. I am very happy for him that he was able to open the game for us," Tuchel said of the Brazil international, who turns 37 on Wednesday.
"His performance even in the first half was outstanding. It was a fantastic performance and well deserved."
Tuchel critical of Chelsea despite win
Although Tuchel was pleased to get the win, he saw enough evidence in the first half that proves his side still have a lot of work to do if they are to compete for major trophies.
"I was absolutely not happy with the first 45 minutes," he said to Sky Sports .
"There were individual performances which were great in the first half from Kepa and Thiago Silva. Even more players were good but in general we lacked intent, energy and relentless in duels and 50-50 balls.
"I had the feeling we wanted to impress by pure skills but in derbies like this it is not always about just skills. It is about aggression, winning duels and performing better as a team.
"We spoke clearly about it at half time. In the second half it was a very good performance and a deserved win in the second half. It was a very good reaction so I am happy with the performance in the second half."
He added: "We are competitive and we want to be competitive. It is no excuse to say we are not ready. We want to produce results and we can. It's what we want at the club. We want to win.
"We are competitive in this level to win already but we still have things to improve. The first half was proof of that. It's good to have these hard situations now and to overcome them. We are able to produce deserved wins so it's a good basis to keep on going."
What next for Chelsea?
Chelsea are in action again on Wednesday, facing Aston Villa in the Carabao Cup at Stamford Bridge.
Three days later, they will host Premier League champions Manchester City before turning their attention back to the Champions League with a trip to Juventus on September 29.