LONDON - Arsenal romped into the semi-finals of the Champions League with a crushing 3-0 home defeat of Villarreal on Wednesday to seal a 4-1 aggregate victory and a last four clash with holders Manchester United. Theo Walcott set the tone for a surprisingly one-sided encounter with an early opener before Emmanuel Adebayor's second goal of the tie on the hour and a Robin van Persie penalty finished off Villarreal who had Sebastian Eguren sent off. Villarreal's hopes of Champions League glory were also ended by Arsenal in 2006. However, while that semi-final meeting between the sides was on a knife edge until the very end, Arsenal were streets ahead of their disappointing opponents this time and could have won by a much larger margin. After the fireworks across London on Tuesday when Chelsea scrambled an incredible 7-5 aggregate victory over Liverpool, Arsenal's fans were spared any anxiety as the rejuvenated Gunners continued their late-season surge that could yet end the north London club's four-year wait for silverware. Thousands streamed out of the Emirates well before the end, their thoughts already turning to Saturday's FA Cup semi-final date with Chelsea at Wembley. "We did very well but we didn't want to be greedy because we have a (FA Cup) semi-final in three days," captain Cesc Fabregas said. "Villarreal were never dangerous and we were always in control. Now let's focus on Chelsea." Adebayor's stunning equaliser in the El Madrigal last week meant a 0-0 draw would have sufficed in the second leg. However, Arsene Wenger's side were clearly intent on killing off Villarreal early and the Spaniards were left reeling by Arsenal's pace in the opening exchanges. "We played to win the game and we played in a very offensive way," Wenger, whose side are unbeaten in 18 Premier League games after a poor start to the season, told reporters. "We are going to enjoy this tonight and then look forward to the challenge of playing United but there are more games to play before that. It's going to be an exciting tie because both sides like to go forward. It will be very interesting." Walcott dazzled all night for Arsenal and gave experienced Spain left back Joan Capdevila a torrid time. After 10 minutes the England winger raced on to a deft flick from Fabregas and coolly dinked a lob over goalkeeper Diego Lopez. Without the commanding midfield presence of injured Marcos Senna, Villarreal struggled to gain a foothold although Arsenal also had virtually their entire first choice defence missing after Bacary Sagna withdrew through illness. Arsenal should have doubled their lead after 28 minutes when van Persie's free kick was saved by Lopez and Adebayor's follow-up header bounced off Arsenal old boy Robert Pires before Gonzalo Rodriguez hacked the ball off the line. Adebayor made no mistake after 60 minutes, slotting past Lopez following a defence-splitting pass from van Persie. The Dutchman then completed the rout from the spot after Eguren was harshly adjudged to have fouled Walcott in the area and was sent off.