Real Madrid moved a significant step nearer to a 34th LaLiga title as Karim Benzema set them on the way to a 2-0 win over Deportivo Alaves.
The gap to Barcelona in second place is back to four points, and it would take a mighty collapse from this position for the teams to swap positions.
Marco Asensio grabbed Madrid's second goal after Benzema's early penalty, and Zinedine Zidane's side could have stretched their lead as a string of chances came their way.
But lowly Alaves contributed plenty to an entertaining game, enough to suggest they can survive in the top flight under their new coach Juan Muniz.
Madrid edged ahead with an 11th-minute spot-kick from Benzema after Ferland Mendy – starting in place of the injured Marcelo – was brought down by Alaves right-back Ximo Navarro.
Benzema, filling in for suspended regular penalty taker Sergio Ramos, calmly fired into the bottom-left corner.
Madrid had by that stage survived a scare when Joselu headed against the crossbar from just five yards and Lucas Perez's follow-up was booted off the line by Raphael Varane.
Joselu squandered another chance when he shot wide for Alaves, who have now lost six straight games to put their place among the elite in unexpected peril.
The visitors to the Estadio Alfredo Di Stefano, being led by Muniz for the first time, continued to ask questions of Madrid's backline.
But the jig was up for them early in the second half, with Benzema fed by Rodrygo before slipping in Asensio to score from close range. To the naked eye, Benzema appeared offside, but VAR replays favoured Zidane's team.
Benzema and Rodrygo saw shots pushed away by Roberto Jimenez as Madrid went in for the kill.
It hardly mattered that they failed to add to their haul, the pressure now overwhelming for Barcelona as they head to Real Valladolid on Saturday.