One Chelsea youngster has now been ranked as one of the best up and coming players in world football right now. This is according to a list compiled by ESPN, who actually rate the Blues man above promising Manchester United youngster Kobbie Mainoo. Mainoo has proven to be one of the breakout stars of the season in the Premier League, and he will almost certainly be part of the side who start against Chelsea at Stamford Bridge tomorrow night. Despite the Blues’ poor season, it has been clear to see that they have a number of promising youngsters available to them, however it seems as if one wil…