English Premier League leader Manchester United has been paired with reigning Spanish La Liga champion Real Madrid in the UEFA Champions League Round of 16, while Arsenal travels to Bayern Munich, AC Milan faces FC Barcelona and Scottish champion Celtic plays Italian champion Juventus.

The four other ties are Paris Saint-Germain vs. Valencia, Malaga vs. FC Porto, Galatasaray vs. Schalke 04, and Borussia Dortmund vs. Shakhtar Donetsk.

Undoubtedly the standout series of the round, Man United vs. Real brings Cristiano Ronaldo back to Old Trafford for the first time since leaving the club in 2009. The global soccer giants have not met in the Champions League since 2003, when Real defeated the Red Devils 6-5 over two legs, with Ronaldo, the Brazilian Ronaldo, scoring a hat trick in the second leg, a 4-3 win for United at Old Trafford.

 Real has won the Champions League nine times, while United has won it twice.