His form has trailed of though, imo. Hasn't been the same player for a few months now.
Six goals and 11 assists to Silva's 5 goals and 12 assists in a very similar amount of games (Mata's 31 appearances to Silva's 30) according to Soccernet regardless of the current form of both players. But when you consider that it's Mata's first season in England playing for a team experiencing their worst domestic campaign for years, I think he's personally more deserving of an inclusion than Silva.
Fair enough. At that points it just comes down to which one was more impressive while watching, and I'll probably still stick with Silva. Could go either way, though.