5 Most expensive transfers of the summer window so far

#2 Cristiano Ronaldo – Real Madrid to Juventus €100 million

Juventus fans celebrate the announcement of Ronaldo's arrival

Certainly, the most speculated and talked about transfer of the window so far, Cristiano Ronaldo has left Real Madrid to join Italian giants Juventus. The Portuguese superstar had an incredible nine years in Spain, breaking countless records, winning numerous trophies, and enjoying a captivating rivalry with Lionel Messi.

It says a lot that Real Madrid turned a profit on the player they signed form Manchester United for €94 million in 2009. Even at 33-years-old, Ronaldo has the potential to play for several more seasons and is sure to help Juventus challenge for the Champions League in the coming seasons. While not the most expensive transfer of this window, it could certainly be the most important for both Real Madrid and Juventus.