Kylian Mbappe fired Real Madrid to a 1-1 draw against city rivals Atletico to keep Los Blancos top of La Liga.
Julian Alvarez dinked home a controversial first half penalty for Atletico on Saturday, but Mbappe was in the right place at the right time to bundle home in his first appearance in the tense derby clash.
Reigning champions Real Madrid lead second-place Atletico by a single point with El Classico rivals Barcelona in third.
Atletico shaded a tight first half but were left holding on in the second period as the hosts stepped up a gear at the Santiago Bernabeu. Jude Bellingham came close to sealing a comeback win as he twice went close with headed chances.
"The team is disappointed because they think they deserved more... but we're happy because we're still leaders," Real Madrid coach Carlo Ancelotti said afterwards. "In the second half we had total control, we had a lot of chances."
Ancelotti opted to deploy his four key attackers in Mbappe, Vinicius Junior, Bellingham and Rodrygo. The star names got stuck in, not always a given in a defensive sense, and the first half was a hard-fought, intense battle with few clear openings for either side.
Atletico were upset when Real Madrid midfielder Dani Ceballos was only booked for an ugly challenge on Pablo Barrios, but it was the hosts who were left raging when referee Cesar Soto Grado pointed to the penalty spot.
Aurelien Tchouameni, covering at centre-back for Madrid with Antonio Rudiger and Eder Militao out, clumsily trod on Samuel Lino's foot in the box.
After a VAR review Soto Grado awarded a controversial penalty, much to Madrid's frustration, with the incident happening after the ball had run past the duo.
Los Blancos attacked Spanish refereeing earlier in the week after they were upset by a decision in a shock defeat last weekend, bringing heavy scrutiny on the officials ahead of the derby. Alvarez took the penalty, the first given against Madrid in La Liga this season, and cheekily executed a Panenka down the middle.
"I can't say I wasn't a bit nervous (with the penalty), but I was sure, I knew what I would do, and it was a great goal for the team," Alvarez said.
"Corruption in the federation," chanted Real Madrid fans in response to falling behind, buying into their club's stance.
Ancelotti refused to talk about the refereeing but appeared exasperated on the sideline as Soto Grado pointed to the spot.
Madrid pulled level early in the second half when Rodrygo broke loose on the right of the box and crossed for Bellingham.
The England international's shot was blocked but Mbappe was on hand to turn home the rebound and score on his first Madrid derby appearance.
Bellingham twice came close to putting Madrid ahead, nodding against the crossbar from Vinicius' cross and then heading straight at Atletico goalkeeper Jan Oblak from a similar position, kicking the post in frustration.
Madrid played with far more fluidity in the second half and pegged Atletico back.
Oblak made a smart save to deny Vinicius after the Brazilian winger burst through the gap between two Atletico defenders and pulled the trigger from a tight angle.
The Slovenian goalkeeper also made fine saves from Rodrygo and Mbappe to ensure the two sides ended with a point apiece.
"We had a good first half, but we weren't relaxed enough in front of goal to (score) more," said Simeone.
"In the end it was a draw in which both teams think they could have taken more from it."
Real Madrid face another big challenge on Tuesday when they travel to face Pep Guardiola's Manchester City in the Champions League play-off round first leg.
Earlier Athletic Bilbao, fourth, beat Girona 3-0 with an Oihan Sancet hat-trick to maintain their Champions League charge.
Antony, on loan from Manchester United, netted his first goal for Real Betis in a 3-2 defeat by Celta Vigo.
