After the points were shared at Camp Nou, the away side were left aggrieved with the officiating.
Real Madrid has publicly highlighted the perceived injustice of multiple unsuccessful penalty shouts following their goalless El Clasico draw against Barcelona on Wednesday.
Raphael Varane had two strong appeals turned down in the first half, the first for a high challenge from Barca defender Clement Lenglet at Camp Nou following a free-kick.
Barca's Ivan Rakitic had grappled with the defender in the seconds before that incident and then tugged Varane's shirt when competing for a corner moments later in the La Liga blockbuster showdown.
Referee Alejandro Jose Hernandez Hernandez let play continue and neither incident was checked using the VAR pitch-side monitor.
Sergio Ramos described them as "pretty clear" penalties and Madrid called attention to the "two controversial moments" in a statement on their website.
It read: "The Frenchman could have had two penalties in the first half but Hernandez Hernandez did not give either of them."
"On minute 17, Varane went to head a corner before Lenglet stood on his thigh muscle in the area, but neither the referee nor VAR (where Ricardo de Burgos Bengoetxea was in charge) deemed it a penalty."
"Two minutes later and following another corner, the central defender had his shirt pulled by Ivan Rakitic, which saw him end up on the ground in the penalty area."
"However, once again, neither the referee or the VAR system decided to award the penalty."
Madrid winger Gareth Bale had a goal disallowed for an offside against Ferland Mendy after half-time as both sides failed to muster a winner.
The stalemate left them level on points at the top of the La Liga standings, but Barca hold the advantage on goal difference, with a five-point gap to third-placed Sevilla.
Real boss Zinedine Zidane became the first Los Blancos manager to go five games unbeaten at the Camp Nou.
Across his past five matches in all competitions at the Catalans' home ground, Zidane has drawn three and won two games to ensure his side have proven difficult visitors for Barca.
The two sides' recent goalless draw was the first 0-0 result between the duo in all competitions since November 2002 - a run of 6235 days.
It was a record-breaking night all round for Real Madrid as Sergio Ramos also became the fixture's most capped player as he started in his 43rd Clasico.