Real Madrid dethroned Barcelona from the leadership of La Liga for the first time since October after grinding out a 1-0 win away at Real Valladolid on Sunday.
Barcelona in contrast suffered a surprise defeat to Valencia on Saturday.
It is 16 weeks since Madrid last finished a round top of the pile and it looked like a scrappy contest at the Jose Zorilla would end goalless until Nacho Fernandez headed in the winner with 12 minutes remaining.
Victory means Zinedine Zidane’s side pull three points ahead of Barca, whose 2-0 loss away at the Mestalla on Saturday under new coach Quique Setien could prove a turning point in a nip-and-tuck title race.
Real Valladolid, who are owned by the former Brazil and Real Madrid striker Ronaldo, are being drawn into a relegation fight after winning only one of their last 12. They stay 16th, five points above the bottom three.
After a scrappy opening 45 minutes, Madrid improved in the second period as the lively Rodrygo tested Jordi Masip and Benzema twice should have scored.
First, he failed to volley in an excellent Isco cross from close range and then rose high to meet Rodrygo’s delivery but headed wide of the post.
Valladolid were retreating and, in the 78th minute, Madrid struck. Toni Kroos’ corner was cleared back out to him and at the second time of asking, he picked out Nacho, who diverted a smart header into the far corner.
Nacho ran over to Zidane on the touchline to hug his coach.
There was a late siege as Valladolid came again in the final minutes, the stadium erupting after Sergi Guardiola tapped in at the back post. But his outstretched right foot was offside, and Madrid breathed a sigh of relief.