Chelsea take on Real Madrid on Tuesday night in the last game of their pre-season tour of the USA. The Blues’ results in their four previous friendlies in America have been mixed. They drew 2-2 with League One side Wrexham in their opening fixture. Enzo Maresca’s side then suffered an embarrassing 4-1 defeat to Celtic but bounced back with an impressive 3-0 win against Club America. Most recently, Chelsea lost 4-2 to reigning Premier League champions Manchester City in a game they actually played fairly well. There have been signs of improvement but the Italian boss will not be pleased with th…