The visitors couldn't have wished for a better start, taking the lead after just five minutes thanks to some poor Villarreal defending.
Sergio Asenjo just managed to collect a poor back-pass, but got the ball stuck between his feet allowing Marica to steal in and slot the ball into an empty net.
The home team responded well and might have taken the lead when Cani drifted past several challenges and into the box, only to see his shot blocked.
Giovani dos Santos then wriggled free and tried a delicate chip which dropped wide for the hosts before they had a penalty shout turned down.
The Mexican came even closer 10 minutes later, capitalising on a fortunate deflection and rounding the goalkeeper, only to see his shot cleared off the line.
Things got a lot worse for the home side minutes from the break when Marica ran clear through the middle before being brought down by Iniguez. The referee had no hesitation and produced a red card for the defender.