The former Valencia captain scored in the 69th minute to complement an already excellent performance for the Yellow Submarine. His outing earned him a 9.3 FC Rating.
Osasuna moved up to 11th in the table after securing a 0-0 draw away at Eibar, largely due to the efforts of goalkeeper Sergio Herrera (8.5), who made no less than six saves to earn his clean sheet bonus.
Gerard Pique (7.8) and Raphael Varane (7.6) didn't deserve to be on a losing side this weekend.
Joining the Clasico pair in defence is Robin Le Normand (7.9), who was on a winning team as Real Sociedad impressively defeated Betis 3-0 away.
As well as Parejo, another player in our line-up put in a cracking performance to ensure the defeat of a former club.
Marc Cucurella (7.5), a former Barcelona B star, was superb down the left wing in Getafe's narrow 1-0 win.
Garcia'a Athletic team-mate Inaki Williams (7.7) scored the second goal in the 2-0 win over Levante, and featured in the centre-forward position.
Making up the rest of the attack is Goncalo Guedes (7.4) and Tete Morente (7.5).