film leaked of raheem sterling inhaling nitrous oxide just a day after he was pictured smoking shisha .
sterling put liverpool 1-0 up after just nine minutes at anfield before missing easy chance in second half .
referee lee mason missed what pundit gary neville described as a ` blatant penalty ' for newcastle 's ayoze perez .
welsh midfielder joe allen then scored his first goal at anfield to put liverpool 2-0 up after 70 minutes .
france midfielder moussa sissoko sent off late on for two bookable offences .
result moves liverpool up to within four points of manchester city in fourth and is newcastle 's fifth defeat in a row .