If Villarreal are to reach the Champions League Final they must score at least two goals against Arsenal on Tuesday night - and that is as many as Arsène Wenger's side have conceded in the entire competition this season.
It is seven months since the Frenchman's defence was breached in European competition.
Thun's Nelson Ferreira did it on September 14 and Markus Rosenberg of Ajax did it 13 days later. Since then the team have rattled up nine consecutive clean sheets - a Champions League record.
Villarreal did not seem unduly disappointed with their 1-0 defeat at Highbury last week. They remained compact, composed and cautious throughout the 90 minutes. But that must change in the return rubber.
"They looked happy with a 1-0," said Wenger before the weekend game with Tottenham. "That's what Thierry Henry saw and called it negative. I don't really think they were negative. But they were a team who never came out and always tried to stop us going forward on the breaks especially.
"They did that well with a lot of tactical maturity. They will have to come out now of course.
"The best way to deal with that is to score [ourselves]. That would be ideal and that's what we'll try to achieve. We are a team who can always score goals. But as well I think that for us it's most important to go there, form a good defensive base every time we go forward and try to win the game.
"It's good because we have as well a few clean sheets, so one defence will have to give in and I hope it will be them.
"It's not the biggest of stadiums. It's a bit like a Highbury but they have a good pitch and when you have good technique that's most important.
"I feel the pace of our game will be the key, we will try to play at a high pace. I think they'll try to up theirs as well so you should see a much more exciting game in the second leg."
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