Set your DVRs, plan your late long lunches, etc. The Champions League is back. If you're a follower of European club football, you're excited as we are. If not, but you plan to watch the World Cup this summer, this is the competition you need to watch to get ready. Here are our previews of this week's four first leg matches, with a focus on which players to watch on each team (and a particular focus on players that will feature prominently at the World Cup this summer): Man City-Barcelona, Bayer Leverkusen-PSG, Arsenal-Bayern Munich and AC Milan-Atlético Madrid.