LONDON -- Kolo Toure scored his first goal of the season in the 41st minute Wednesday night, giving Arsenal a 1-0 win over Villarreal in the first leg of the European Champions League semifinals.
After dominating with a half-dozen chances, Arsenal took the lead after Thierry Henry's corner kick was deflected out of the penalty area. He regained the ball and passed to Alexander Hleb, who chipped the ball to Toure.
Toure then slipped it behind goalkeeper Mariano Barbosa from close range.
"The next six days really define our season," Arsenal manager Arsene Wenger said. "We are confident we can do it."
Arsenal plays at Villarreal next Tuesday in the second leg of the home-and-home, total-goals series. In the other semifinal, Barcelona is home next Wednesday against AC Milan after winning the first leg 1-0 in Italy.
"We didn't play well and that's why we lost," Villarreal forward Diego Forlan said. "We need to score and not let them score -- and it's not going to be very easy. We tried to do our best and we could not get forward."
Arsenal is trying to advance to the final of Europe's top club competition for the first time.
"We have nothing so far," Henry said. "We are 1-nil up, but they really made it difficult for us."
Arsenal has not allowed a goal in a nine straight Champions League games, one more than the previous mark set by AC Milan. It was the last European game at Highbury -- Arsenal is moving next season to a new 60,000-seat stadium a few blocks away in north London.
Arsenal escaped a penalty late in the first half when Gilberto brought down Villarreal's Josi Mari in the penalty area.
"I wasn't happy, because there was a penalty today that we should have had," Villarreal coach Manuel Pellegrini said.