The French striker put himself back in contention for a starting spot in Jose Mourinho's side with two goals and two assists as Los Blancos emerged victorious
Los Blancos weathered an early storm to take a two-goal advantage into the break courtesy of goals from Karim Benzema and Kaka. Jose Rodriguez added a third for the Liga champions and Benzema grabbed his second to dampen the hosts'spirits after Javi Lara had struck from a superb free kick for the hosts.
Jose Mourinho opted to rest the majority of his star players for the fixture, with Michael Essien and Raphael Varane the only survivors from last weekend's 5-0 win over Mallorca.
This offered players such as Kaka, Benzema and Jose Callejon a chance to stake their claim for a chance in the first team, but drawing on the buzz of anticipation around the small ground, Alcoyano started brightly and seemed to catch Real Madrid by surprise.
Javi Lara looked extremely lively on the ball and with just five minutes played it took a last-ditch clearance from Nacho to stop Alcoyano from converting for an early lead.
Yet for all the hosts' positive attacking play, it was an error at the back that enabled Los Blancos to break the deadlock with their first attack of the night.
A long ball forward was not dealt with by Javi Selvas and in his attempts to recover for his team-mate, Arkaitz headed the ball back into the danger area. There Benzema capitalised, showing his goal-scoring instinct to steal in ahead of the keeper and nod into the net.
Mourinho's men began to settle and after Morata had a goal ruled out for offside, Madrid made it two in the 35th minute. Benzema laid the ball off to Kaka who drove a precise left-footed shot from the top of the box into the far corner.
Alcoyano began the second half in an almost identical manner to that of the first, putting the visitors under pressure and drawing free kicks. However, they were unable to make their chances count as the waves of crosses were sent back where they came from by white shirts.
With Madrid lacking urgency, the visitors were given more freedom to attack but neither Pierda nor Omar could make the most of some decent chances shortly after the hour mark.
However, Los Blancos soon showed how clinical dinishing can be decisive as Benzema poked the ball to Jose Rodriguez who then bent in a brilliantly controlled finish despite the best efforts of Alba.
There was something for the home fans to cheer late on, though, as Javi Lara got a deserved goal with an exquisitely struck free kick that beat Adan at his near post 14 minutes from time.
But Madrid were not done and they managed to take a more commanding lead as Benzema slotted home his second following a sumptuous one-two with Kaka.
Alcoyano now have a trip to the Santiago Bernabeu to look forward to on November 27, though the three-goal deficit may be too much to overturn.