Not all transfers are created equal, especially midway through the European season in the January window. Indeed, some moves would cause shock waves through the game if they happen. They probably won't, but here are some that could do just that.
Kylian Mbappé: Paris Saint-Germain to Real Madrid
The big one. Mbappé's contract at Paris Saint-Germain expires in the summer and, as yet, there are no signs he is set to pen a new one. The 24-year-old reportedly wants to move to Real Madrid, but is loath to do so on a free transfer out of respect for his club, so that means the January transfer window is likely to be the last chance he could do so for a fee -- unless he agrees to a new deal with an achievable release clause, of course.