Manchester United can start negotiating with four superstars over free transfers in January

Back-to-back losses to Brighton and Brentford and fan unrest with the club's owners prompted the Glazers to dig a little deeper and fund the arrivals of Casemiro and Antony for a combined fee that could surpass 150million.

United signed Tyrell Malacia, Christian Eriksen and Lisandro Martinez earlier on in the window, all of whom have established themselves as first-teamers in the opening weeks of the season.

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Martin Dubravka's loan arrival from Newcastle concluded United's summer business as far as incomings were concerned, yet the rebuild is not over yet and United will return to the market next year.

Given the amount United spent in the summer just gone, they will welcome any possible bargain additions and they could come in the form of free agents next summer.

From January, United will be able to negotiate with players outside of the Premier League whose contracts are due to expire next summer. Here are some of the superstar names who currently find themselves in that position:

Jan Oblak (Atletico Madrid) – David de Gea is one of United's highest-paid players and his contract is up next year. Although United have the option to extend De Gea's deal to 2024, it might be tempting to part ways and bring in a 'keeper on a cheaper deal. Oblak would certainly be an excellent replacement.

Toni Kroos (Real Madrid) – United have just signed one of the great Real Madrid midfielders and another could be available for free in under a year's time. The Kroos-Modric axis appears timeless but in reality it isn't, and Carlo Ancelotti is already working on nurturing Madrid's midfield for the next decade with Aurelien Tchouameni and Eduardo Camavinga. David Moyes wanted Kroos – could Ten Hag get him?

Other available players: