The list of clubs pondering the possibility of signing wantaway star Marcus Rashford from Manchester United in January is growing day-by-day. Yet, despite that apparent interest, there is one constant problem.

Rashford has played 24 times for United this season, scoring seven goals. Since Ruben Amorim's appointment as Erik ten Hag' successor in November, he has appeared only six times and has also missed the previous five games.

There's an expectation that the 27-year-old will depart Old Trafford this month in hope of rediscovering his form. After rejecting a mega-money switch to Saudi Arabia in hope of staying in Europe, Rashford isn't short of interest from some of the continent's top leagues, either.

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Talks over an initial loan move to join AC Milan have developed this week with Juventus, Tottenham and Borussia Dortmund all linked with a potential swoop, too. On Friday, it was emerged that Barcelona could land the England international after sporting director Deco decided that a move would be viable.

However, Rashford's salary is a concern. The forward reportedly earns £325,000-per-week and is one of United's highest-earners. Every report linking him with a move away has mentioned that problem in potential discussions over how his salary will be split for the second part of the season.

Reports in Spain reckon Barcelona need to "generate some salary space" in order to sign Rashford and to do that, they could look at selling some big-earners like Ronald Araujo, Ansu Fati or Eric Garcia. If they can't, a move to the iconic Camp Nou seems out of the question.

It's a problem that United are paying the price for, literally. Rashford's wages will be a worry if the time ever comes for a permanent deal to be struck up. In fact, it's an issue running through Amorim's squad.

In a window in which United need to sell before they can buy, some players who aren't part of the Portuguese's plans are struggling to secure moves away. Casemiro reportedly earns £350,000-per-week while Antony brings in around £200,000-per-week. Both players aren't part of Amorim's ideas and could easily be allowed to leave before the window slams shut.

If the worse-case scenario plays out for United this month and neither of those three players leave, United will be at fault. The big wages they have offered players has come back to haunt them. In a sense, they have learned from their mistakes with the recent news around Kobbie Mainoo - but that comes with its own concern.

The Academy graduate is reportedly keen on a new contract at Old Trafford and a £200,000-per-week has been touted. Negotiations haven't gone perfectly, and that's likely to be down to the club's desire to bring down their wage bill. The problem they have, there are players on better deals who aren't truly worth it.