How does it work?Thirty-six sides entered into the new "league phase" and now just four remain with a month-and-a-half to go in the UCL campaign.Barcelona, Paris Saint-Germain, Arsenal, and Inter Milan are through to the semifinals,

Paris Saint-Germain travel to England for the third time in the UEFA Champions League knockout stage taking on Arsenal in the first leg of the semifinals. Luis Enrique's team faced Arsenal in the league phase earlier in the season losing 2-0.

Paris St. Germain will be a tougher proposition for Arsenal when the sides meet for a second time in this season’s Champions League, the French club’s manager, Luis Enrique, said on the eve of their semifinal first leg on Tuesday.