Transfers are unpredictable. Despite all of the scouting, research and negotiating that goes into bringing in a quality player to a top team, no one can truly know how it will pan out until a ball is kicked.
Sometimes, though, the very worst can happen. Whether it be through poor performances, managerial fallouts, or personal issues, some big-time moves simply don't work. And this season, there have been plenty of duds.
Whether it be the free-spending ways of Paris Saint-Germain, tight budgets of Barcelona or the usually-shrewd schemes of Borussia Dortmund, clubs around the continent have got it wrong. GOAL, therefore, takes a look at some of the worst deals made in European football over the past year...
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