9. Michael Owen (Real Madrid to Newcastle £16.8m)
Michael Owen may have literally burst onto the scene, but by the time Newcastle snapped him up, he was a shell of his former self. He arguably never reached his full potential after a hamstring injury six years previously whilst playing for Liverpool, and a move to Spanish giants Real Madrid never really worked out. Nevertheless, the Magpies decided to break their transfer record to bring him back. Unsurprisingly, he failed to capture the magic of his early years, scoring just 26 goals in 71 games, and being part of the side that was relegated to the Championship in his final season with the club.