Marcelo was sacrificed for Ferland Mendy while Nacho replaced the injured Sergio Ramos, as Real went for two changes from the midweek encounter against Elche.
Real wasted no time to go ahead when a cross to the back-post from Marco Asensio on six minutes found Lucas Vazquez who gladly headed into the near corner.
Los Blancos didn't sit back after going ahead but looked for a second towards halftime with penetrative balls out wide and through the middle, but Celta dropped deep to avert every move.
Dani Carvajal nearly gave Los Blancos a second in sublime fashion minutes to the break from a first-time volley on the edge of the area, but in the end fired wide.
A troubling injury five minutes into the second half ended Iago Aspas' evening on the side of Celta, with Fran Beltran introduced as his replacement.
Nevertheless, Real extended their tally on 54 minutes when Asensio got on the end of a cross-field ball across the six-yard area to blast into an empty net following possession turnover from the visitors.
The Sky Blues were left to chase shadows thereafter, as a snap-shot from the far side by Karim Benzema fizzled wide of the far corner from a pass by Toni Kroos.
Zinedine Zidane's side began dropping deep towards the final minutes, with Celta gunning for a glimmer of hope by throwing numbers in attack.
Benzema should've added a third goal in the final minute of regulation following a darting run across the area, but hoofed over the crossbar, leaving Real to victory and top spot nonetheless.
