The Brazilian is one of the club's highest earners with an estimated weekly wage of £350,000.
But after making just 11 Premier League starts this season, the writing appeared to be on the wall for the midfielder.
Casemiro was strongly linked with a January exit with a move to Sadui Arabia hotly tipped.
That interest didn't lead to a move, however a summer offer always felt inevitable.
With 18 months left on his contract, staying with the Red Devils would cost the club an estimated £27million.
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But according to the Real Madrid legend, a move away from Man United at the end of the season is not on the cards.
In an interview with Spanish outlet AS, he said: "I have to keep doing what I'm doing, with a lot of respect and education. Of course, I'd like to play more, of course.
"I don't know any player who doesn't want to play and help. Also, I'd like to help the club at this time.
"I approach things with respect for my teammates and the technical committee.
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"And above all, I respect United, a club to which I'm very grateful.
"I have a year and a half left on my contract and I'd like to fulfil it here in Manchester.
"I'm comfortable here and so is my family. They've adapted, we speak English. I'm very grateful to the Old Trafford fans and to the club. I'm happy at club level.
"I'm young and I still have a lot of life left.
"I'm now 33 years old and in this era I'm 28 years old. Nutrition, physical preparation, everything lengthens a footballer's career if you take care of yourself.
"That's why Cristiano [Ronaldo] at 40 years old continues to score 50 goals a season."
Casemiro joined Man United in the summer of 2022 for a fee worth £60million after ending his nine-year stay in Madrid.
While putting in some brilliant performances in his first season, the Brazilian has fallen down the pecking order more recent.
The 32-year-old started Ruben Amorim's first two games in charge against Ipswich and Everton, but was an unused substitute for the following five games.
He was then restored to the starting XI for the 1-0 defeat to Tottenham on Sunday following injuries to Kobbie Mainoo and Manuel Ugarte.