Fans' favourite Torres was the centre of attention at the Vicente Calderon after rejoining the Spanish champions from Milan last week, having agreed a loan deal until the end of next season.
However, it was Raul Garcia from the penalty spot and Jose Gimenez who made sure of this first-leg triumph.
Raul Garcia's 58th-minute opener came after he had been hauled to the ground by Real captain Sergio Ramos in the area, before Gimenez headed in the second 14 minutes from time.
Torres was given a hero's reception again, although he failed to have too much of an impact during his hour on the pitch.
Valencia needed a late penalty to overcome a resilient Espanyol side 2-1 at the Mestalla.
A curling effort from Jose Gaya gave Valencia the lead after 11 minutes but Espanyol drew level when Christian Stuani stroked home from close range on the hour-mark.
With time winding down, on-loan Manchester City striker Alvaro Negredo made no mistake from the spot.
In the day's other games, Almeria midfielder Verza scored for both sides as Getafe held the Andalusian side to a 1-1 draw while Villarreal brought Barcelona conquerors Real Sociedad back down to earth with a 1-0 win at the El Madrigal.
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