Following Ruben Amorim's decision to start Manuel Ugarte and Kobbie Mainoo on the bench for the Europa League win over Rangers, opportunity knocked for Manchester United's other midfielders.

Ugarte and Mainoo have established themselves as Amorim's first-choice midfield duo in recent weeks and had started each of the last four games prior to Thursday night's Scottish invasion.

But given the strain United's fixture schedule is currently putting on the squad, the Portuguese chief was left with no choice but to make some tweaks. He admitted ahead of last weekend's defeat to Brighton & Hove Albion that it was "impossible" to go through this period without rotating.

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Having given both Ugarte and Mainoo four consecutive starts, the visit of Rangers was a timely opportunity to freshen things up. Christian Eriksen secured his first start since the 2-0 defeat to Newcastle United at the end of December and Toby Collyer was rewarded for his recent cameos by making just his second start for the club.

The latter has been growing in stature in recent weeks, so much so United no longer have any plans to let him leave on loan this month. It was previously understood that he was open to a temporary switch to a Championship club in pursuit of regular minutes.

Instead, he has leapfrogged Casemiro in the pecking order. The Brazilian is still waiting to be handed his first minute(s) in 2025 after playing the role of an unused substitute for the fifth game running on Thursday evening.

The midfield enforcer, who last played when he started the defeat to Newcastle, now finds himself on his longest run without making an appearance when he has been available for selection since joining the club in August 2022. He has racked up just 350 minutes worth of football since Amorim replaced Erik ten Hag, featuring in just six of his opening 16 games in charge.

Explaining why opportunities have recently dried up for the Brazilian, Amorim said: "He has to be the characteristics and then I have to choose the player with characteristics that I see the game. 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."

Despite being on the decline prior to Ten Hag's exit at the end of October, Casemiro was often a regular starter under the Dutchman. He was excellent in his first season at Old Trafford, providing United with the steel and grit in midfield that had been missing for several years.

The drawback for United was that they signed him at 30 years of age and tied him down to a long-term contract. They also paid an initial fee of £60million.

As brilliant as he was in his maiden season at the club, Casemiro, through no fault of his own, was never going to be a long-term option for United. Ugarte, 23, was signed as a long-term replacement just two years later.

Turning 33 in a matter of weeks, United now have a player on their books that is finding game time increasingly hard to come by under the new regime. What's more, he still has 18 months remaining on his contract.

With that in mind, United find themselves in a position where time is running out to sell him and recoup at least some of the £60m they spent on him two-and-a-half years ago. It is no secret they are going to have to accept a huge financial loss, but that was a risk they had to consider.

Once a player reaches the final 12 months of their deal, suitors will attempt to drive the asking price down. It means United will be looking at an even lesser fee if they wait until the summer to cash-in.

With a little over a week of the January window remaining, United should be doing everything they possibly can to find a buyer for the midfielder. He has regularly been linked with clubs in Saudi Arabia and they are no strangers to signing of one of the game's most established names.

There is little sense in retaining a player that clearly isn't in the head coach's plans. Getting him off the books in the next nine days would save United a substantial sum of money in wages and bank them a transfer fee.

This is where Ineos' desire to become more proactive in the seller's market needs to come to fruition.