Drenthe's U21 performance wasn't OK, it was fantastic... just because everyone else played crap doesn't mean his performance was only showed to be good because of that. His crossing and dribbling was phenomenal as well as his pace and strength.
Of course a signing shouldn't really be based on 1 good tournament but he's shown he's got potential... and these days u have to pay a lot for potential so they got a great deal.
Look at what Chelsea had to pay for Mikel, what United had to pay for Andesron & Nani, what Liverpool had to pay for Babel...
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