Giuseppe Rossi is the marksman that Arsenal will have to keep an eye on. He has scored a dozen times in the Liga and three in the CL. Argentinian Ariel Ibazaga is Villareal's playmaker along with Cani, who gets back to squad duty after injury.
However, Joseba Llorente is the X factor. He has proved to be a super sub providing four goals including a hat trick against Danish side, Aalborg. His link up with Ibazaga scored the winner against Panathinaikos marching them to the CL quarterfinals.
Marcos Senna's defensive organization was a major factor in Spain's Euro win and he has proved that Villareal are tough to beat at El Madrigal. In the Liga, they have won nine games and lost just two.
There is a silver lining for Arsenal.
Villareal have conceded a number of late goals which have resulted in victory snatched away from them. Defensive lapses cost them wins against Osasuna, Atletico Madrid, and Malaga.
Arsenal should take note of that and keep applying attacking pressure even if they do go a goal down. If Arsenal can come up with a draw then they are in good position in the return leg because Villareal are not a good road team and have the worst record amongst the top four Liga teams with just four wins and 23 goals conceded.