#1 Barcelona vs Juventus
If there is any battle in football that will remain unsettled forever it is Ronaldo vs Messi. The two have met once in Champions League final in 2009. Messi emerged victorious with Barcelona by beating Ronaldo's Manchester United.
Since then these two have met in every season in La Liga in the famous El Classicos. Ronaldo's move to Juventus means the only way to see these two against each other is in the Champions League.
Ronaldo will be seeking to win his fourth Champions League title in a row and sixth overall. He will also become the first player to win it with three different clubs.
Messi, on the other hand, will try to end his spectacular season so far on a high. With a hand already on the European Golden boot, a European title will make a perfect end to Messi's first season as Barcelona's full-time captain.
Both Barcelona and Juventus have a foot already on their league titles. A European glory will be as important for the teams as it is for these individual players.