4) Manchester United – Cristiano Ronaldo – £67.5m

Ronaldo

The Red Devils beat off a lot of competition for a certain Portuguese teenager’s signature all the way back in 2003 and they sold him on for a large profit six years later.

United would have loved to have kept hold of Ronaldo, considering his exploits for Real Madrid. The forward may now have returned to Old Trafford but he is way past his peak.