Ruben Amorim has suggested Casemiro no longer has the "characteristics" to start regularly for Manchester United.

Casemiro, 32, has started in four of Amorim's 16 matches in charge and has been an unused substitute on ten occasions. The midfielder started in all four matches under caretaker manager Ruud van Nistelrooy.

Amorim started Toby Collyer alongside Bruno Fernandes in midfield in the 2-1 Europa League win against Rangers, while Christian Eriksen was recalled as one of the two No.10s. Casemiro, whose United contract expires in 18 months, is now effectively their sixth-choice midfielder.

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"He has to be the characteristics and then I have to choose the player with characteristics that I see the game," Amorim explained. "So it’s just that.

"I have to make some choices. I want to play a style of game that is sometimes different from other coaches and I have to choose based on that, that’s all."

Amorim admitted he is unsure if Marcus Rashford will stay beyond the closure of the winter transfer window. Rashford has not played in United's past ten matches and was in attendance in his hospitality box for the Rangers tie on Thursday night.

The winter window closes on February 3 and Amorim appeared to think its closing date was next Friday. "I don’t know," he replied when asked if Rashford could be reintegrated. "I really don’t know.

"Guys, it’s eight days. We will see in the end of the window what happened. And then we will talk about that in the moment."

Bruno Fernandes became United's joint-top scorer of the season on nine goals with his 92nd-minute winner against Rangers. The 30-year-old did not score this season until the club sacked Erik ten Hag but Fernandes has been influential in recent positive results against Manchester City, Liverpool, Arsenal and Rangers.

"I think he’s a top player," Amorim added. "And then people talk a lot about his frustration, always with his arms in the air. Sometimes it’s not a good thing to see but you have to see the other side.

"When you are under pressure, he’s always the guy that wants the ball, he’s always available. And that is so important. Especially in the Premier League.

"And then he can run. And he runs a lot. He fights a lot. You have two sides and I have to help him manage both situations. But we are lucky to have a player like Bruno Fernandes.

"Sometimes he makes mistakes - like me last week. But he’s really important and he has passion. This is so important to be a football player."