Erik ten Hag believes Casemiro has injected a winning mentality into Manchester United since arriving from Real Madrid.
Sunday's Carabao Cup triumph — which ended a six-year trophy drought for the Red Devils — means the Brazilian has now won his last nine major finals and 13 of 14 over the course of a glittering career.
His grateful manager was delighted to see the 31-year-old's performances rewarded with an entry into the FIFPro Team of the Year on Monday.
He said: "We are so proud of him. I think he showed how important he is and how he contributes to our team — in the dressing room, not only on the pitch.
"He is important, everyone can see that, but also around to construct the climate which is necessary to win trophies, and he is showing by example the squad all the example on Sunday.
"And it’s great to work with him. We are so happy with that, it’s a big reward, I’m so happy for him to be rewarded to be in the World Team of the Year. That is really a reward and so wonderful."
United were back in training 19 hours after lifting the trophy and Ten Hag told his stars they have to be prepared to suffer as they continue their pursuit of glory.
He added: "It’s part [of football] if you want to be successful and if you want to be successful, it demands a lot, that demands a lot of high standards and a lot of determination.
"It demands always sacrificing and suffering. It’s not going without because this is football. When you go to the limits, you feel pain. You have to deal with that pain. When you celebrate, you forget all the pain."
