I've been having a think about Lovren and have come to the conclusion that his problems are mental.
It's what goes on between his ears after he makes a mistake.
He's big, strong, quick (for a CB), can pass, tackle and is decent in the air, so he has the physical attributes, but his mentality seems to be lacking.
Put it another way, most players who make a mistake, shrug it off and get on with things.
Lovren makes a mistake, he seems to obsess over it and then try too hard to put it right, leading to more mistakes.
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