Real Madrid restored their eight-point lead at the top of La Liga as they beat city rivals Atletico 2-0 to claim their 10th straight win in all competitions.
Karim Benzema opened the scoring with a brilliant 16th-minute volley - his 13th goal of the season - and Marco Asensio added the second to leave fourth-placed Atletico trailing their rivals by 13 points.
"We are favourites today, of course, you can say that," said coach Carlo Ancelotti on the title race. "But if you relax it can cost you dearly. We have to keep going, to get closer to winning it as soon as possible."
The home team were in total control from start to finish with the Santiago Bernabeu crowd chanting "Ole" in unison when there were still 25 minutes to play in the second half.
It was their fourth consecutive game without conceding a single goal.
Fan favourite Vinicius, who got a standing ovation when receiving La Liga’s player of the month trophy before the game, is yet to score a goal against Atletico in his four seasons in Spain, but on Sunday he turned provider for his teammates.
He started the counter-attack that ended with Benzema's opener, stealing the ball in midfield and sprinting all the way up-front to receive a pass from Asensio and cross for Benzema to smash a volley into the net.
After the break, he led another counter, showing good vision to feed the ball to Asensio to score.
“To win a derby is very important to our fans and I bet they left the stadium really happy,” Asensio said.
The defeat was a blow for Atletico, who have not won a Madrid derby in the league since February 2016.
"The title race is still alive," insisted coach Diego Simeone. "There are a load of matches left. Madrid have a lot of points, it's true, but La Liga is complicated."