Atletico Madrid coach Diego Simeone was left frustrated with VAR after Casemiro was not penalised for appearing to handle the ball in the penalty area during Saturday's 0-0 draw at Real Madrid.
Simeone's side claimed a deserved point at the Santiago Bernabeu, but things could have been even better had they been given a first-half penalty for an apparent handball.
Filipe Luis picked out the run of Koke in the 31st minute and the Spain international's subsequent cross was blocked by Casemiro, with the ball striking his arm.
Despite VAR being available in La Liga this season, the incident was not reviewed and Atletico were denied a great opportunity to take the lead, leaving Simeone irritated.