Coach Zinedine Zidane kept faith with Luka Jovic alongside Karim Benzema in the starting line-up, and the Serbian striker missed two good chances in the first half as he blasted one fierce drive just over the crossbar and poked wide on another occasion.
Fede Valverde, who had opened the scoring in Madrid’s 3-2 win at Real Betis on Saturday, also came close as he forced Roberto Jimenez into a fine save in the opening 45 minutes.
Jovic threatened again with a header in the second half as Roberto got down low to parry and Casemiro smashed the rebound against the crossbar.
But Madrid were lacking some pace and verve and it was no surprise when Zidane made a treble change, sending on Vinicius and Marco Asensio for Isco and Jovic, with Dani Carvajal also replacing Alvaro Odriozola.
Los Blancos immediately looked more threatening in a 4-3-3 formation and the goal arrived as Vinicius found himself in space to beat Roberto after 65 minutes.
The Brazilian had looked to be in an offside position, but the ball had been deflected into his path off a Valladolid defender and he was therefore onside.
The visitors also had chances and Madrid had Thibaut Courtois to thank for fine saves from Shon Weissman and Raul Carnero.
Vinicius missed a great opportunity to add another deep into added time on a breakaway attack, getting his shot all wrong.
That was the final kick of the game and Madrid saw out a 1-0 win in their first fixture at home this season to make it seven points from nine so far in LaLiga.
Valladolid, meanwhile, have just two points from their opening four games in 2020-21.
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