I agree with prongs.
We perhaps need a full back but we do have simpson and the other evans too. It depends really whether fergie sees them as being potentially world class.
I dont think neville will have too many seasons ahead of him but in the RB position we will have Neville, Brown, Simpson and perhaps oshea for cover. For left back we have Evra, tweety and perhaps simpson and oshea for cover. One class full back, perhaps one that can play on both sides might be enough imo.
I would say we definitely need another striker and he doesnt have to be young. An experienced one might actually prove the more successful short term but if fergie wants to have a strike force he wont really need to update much, a young striker might be the better option long term. Perhaps we get both a young striker and a more experienced center forward

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tbh, i doubt very much it would be a midfield player, were a bit crowded in midfield.