The list includes La Liga and Bundesliga stars
With Manchester United having thrown enough money at their attack to make it work again, they are now looking to move on and improve their defence.
The Red Devils have been linked to a number of top names over the last month, with moves looking likely to happen in both January and the summer.
Here are four of the most heavily linked players to Old Trafford…
Man United Unsure About Permanent Move for Radamel Falcao
Manchester United Star Wants To Complete Transfer To Real Madrid
NK Maribor v Chelsea: Live Football Streaming And Champions League Preview
Aymeric Laporte, Athletic Bilbao
The French centre-back has been linked with the Old Trafford side by the Metro.
He would be available for £32 million pounds and at 20-years-old could be a long term option for the Red Devils. He would be an improvement on the current crop of centre-backs, with Phil Jones and Jonny Evans currently finding it hard to fit in to the new style of play being played by manager Louis van Gaal.