Thomas Tuchel has praised Emerson Palmieri for shelving his personal ambitions to help foster a new squad spirit at Chelsea.
Blues boss Tuchel conceded he sent Emerson into the closing stages of Wednesday's Champions League clash with Atletico Madrid mainly as a "thank you" for his positive attitude.
The Italy left-back quickly returned the favour, scoring Chelsea's second goal as they secured a first Champions League quarter-final in seven years.
Emerson was mobbed by his team-mates after sealing the Blues' 2-0 win at Stamford Bridge and 3-0 aggregate victory over Atletico in the last-16 tie.
And Tuchel praised the former Roma defender for never once letting his head drop, despite being behind Ben Chilwell and Marcos Alonso in Chelsea's left-back pecking order.
"I'm so happy for him, the guy suffers all the time from my decision," said Tuchel.
"We have three players for one position with Marcos Alonso, Ben Chilwell and Emerson. So we started to play with a back three and chose different players so he only had the chance to show up in one cup game, which he did.
"After some days where he needed to settle to new information and a new style, he is training with an unbelievable effort. He is one of the nicest guys you can imagine.
"He's always friendly, with unbelievable qualities. It was necessary to give him a reward and give him some minutes as a thank you for his attitude.
"It is the perfect example. You see what comes back, we get such a big reward, everybody celebrating and everybody happy for him because I truly believe everybody in the group feels what he is doing for the group.
"It is not easy because he puts his personal situation aside and he plays his role which is to give 100 per cent, be super professional and at the same time super nice.
"He never lets anybody down with a bad mood. This is fantastic.
"I need to find new rewards for him. I said that to him that I am very happy and grateful and thankful for him that he could show up today and it is a pleasure to have him."
Tuchel boasts the longest unbeaten start of any Chelsea manager after stretching the run to 13 matches.
The Blues have leaked just two goals and kept 11 clean sheets since the German replaced Frank Lampard at the helm.
Atletico might top LaLiga's standings, but Diego Simeone's side had precious few answers to Tuchel's disciplined and highly impressive Chelsea.
Hakim Ziyech opened the scoring after a lightning counter-attack, before Emerson's late strike sealed Chelsea's place in the last eight.
Tuchel might still see Ziyech as a work in progress to adapt to his specific tactical style, but hailed the former Ajax man's performance on a big night for the Blues.
"He suffers a little bit with our style, he needs to adapt to the structure and be more reliable with the ball," said Tuchel.
"And he needs to find a better rhythm when to take the risk and not to take the risk but I am super happy. This was reliable from him.
"He is a hard-working guy up front and I am happy that he could finish the transition with Kai (Havertz) and Timo (Werner), the three were all involved and it was a nice and decisive goal."