Villarreal claimed a narrow advantage in their Europa League semi-final against Arsenal with a 2-1 home victory in the first leg on Thursday, although they will feel frustrated at letting the London club off the hook.
First-half goals by Manu Trigueros and Raul Albiol put the Spanish club in command and it looked bleak for the visitors when Dani Ceballos was sent off just before the hour mark.
Arsenal were rocking and needed keeper Bernd Leno to avoid them slipping further behind but they were thrown a lifeline when Nicolas Pepe converted a 73rd-minute penalty.
A chaotic game took another twist as Villarreal were also reduced to 10 men when former Tottenham Hotspur player Etienne Capoue received a second yellow card.
Villarreal, coached by former Arsenal manager and Europe League specialist Unai Emery, maintained their 100% home record in the competition this season.
But the tie remains delicately balanced ahead of next week's return in London.