4. Ander Herrera (Athletic Bilbao)
No one quite knows what went wrong with this signing, but a move to sign talented midfielder Ander Herrera from Athletic Bilbao fell through late on deadline day, leaving United without a genuine replacement for the creativity offered by the retiring Paul Scholes. The Red Devils are widely tipped to move for the 24-year-old again in January, but for now it is worrying for Moyes that he failed to bring in what could have been such a crucial addition for the entire season.
Herrera is just one of many players linked with United in that position this summer, though he seems to be who they actually came closest to landing, and the bizarre circumstances surrounding his failed move almost sum up the whole summer for the club.