The extra defender is to protect pirlo .....in a 4-3-3 the its a cdm that sits behind when in between of 2 cbs when fullbacks go and attack ..like for barca busquet does to break the counter attacks....pirlo cant do that so we have 3 at the back.
If we had an extra midfielder i'd be up for benching Pirlo anyway in games like this. His world class free kicks keep masking his very poor European performances. He is a legend but sadly doesn't have the legs for intense games. People can literally walk past him providing they don't walk within 2 yards of his personal space.
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