2012 Isco
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Isco was named the Golden Boy in 2012 off the back of his exploits with Malaga and this earned him a move to Real Madrid in the summer of 2013 for a fee believed to be in the region of €30m.
With Los Blancos, Isco has starred, helping the club win four UCL titles, including three consecutively, but has constantly struggled for gametime and is reportedly at loggerheads with head coach Santi Solari, with reports indicating that he is unsettled at Real Madrid with him being a constant target of jeers and boos from the Bernabeu crowd.
Verdict - Having been on his way to greatness, Isco is currently experiencing a lull in his career
2013 Paul Pogba
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After making his name at Juventus, Paul Pogba was re-signed by Manchester United in the summer of 2016 for a then world record fee and it was believed that the Frenchman would be the on field leader to take the club back to its previous heights.
However, two-and-half years down the line, it is still yet to fall in line for Pogba as he has faced criticisms for his inconsistency and showboating.
He has fallen out of favour with Jose Mourinho and Pogba currently finds himself out of the starting lineup with reports emanating that he is on his way out of Old Trafford.
Pogba is no doubt a decent player (his performances in France's World Cup win as well as his displays for Juventus which saw him voted into the FIFPro XI for 2015) are proof of this and it is a shame that he is undergoing his current travails.
Verdict - Might need to leave Manchester United to fulfil his potential