Porto, Portugal (My Sportsbook) - Cristiano Ronaldo's brilliant goal in the sixth minute was enough to lead Manchester United to a 1-0 win over FC Porto at Estadio do Dragao on Wednesday, giving the defending champions a 3-2 aggregate win in the Champions League quarterfinal matchup.

Porto entered the match with an 11-game unbeaten streak at home against English opposition, but Ronaldo struck from 35 yards out early in the game, and the hosts were unable to break down the United defense despite a number of good chances.

Sir Alex Ferguson's men extended their unbeaten streak in the Champions League to 23 games with the win, and they will now meet Arsenal in the semifinals after the Gunners recorded a 3-0 win over Villarreal on Wednesday.

Theo Walcott scored 10 minutes into the game and Emmanuel Adebayor added a second goal on the hour mark before Robin Van Persie converted from the penalty spot nine minutes later to give Arsenal a 4-1 aggregate victory.

The first leg saw Porto take the game to United and seize an early lead, but the Red Devils reversed things on Wednesday and went in front after six minutes.

Anderson played the ball to Ronaldo 40 yards from goal, and after taking one touch, the reigning World Footballer of the Year fired a laser into the upper left corner of the net, leaving goalkeeper Helton with no chance to keep it out.

It was a stunning blow to the home side, but they almost answered in the 20th minute as Bruno Alves sent a free kick over the wall from 30 yards but saw it curl wide of the left post.

Porto suffered another blow in the 29th minute when Lucho Gonzalez had to be taken off with a leg injury, while United almost doubled its lead one minute later.

Dimitar Berbatov sent a cross to the back post from the right wing and Ryan Giggs was on hand to send a low half-volley on goal. However, Helton got down to make a good stop.

Another set piece provided an anxious moment for the visitors in the 41st minute as Bruno Alves got his head on a free kick from Raul Meireles and sent it wide with goalkeeper Edwin van der Sar left standing in the middle of the goal.

Nemanja Vidic then had a glorious chance to put his side up two goals right before the break from a corner kick, but squandered the opportunity.

Giggs played the ball to the near post and it was flicked into the six-yard box by John O'Shea. Vidic was positioned in front of goal and lunged to get a foot to the ball, but he managed to put it over the net from a few yards out.

Porto started brightly in the second half and they had a good chance from a free kick with Hulk getting plenty of pace on his shot from 25 yards, but it was hit straight at Van der Sar.

The United keeper then allowed a corner kick to sail over his head and to the back post for Rolando, who headed over the net, while United's first good look at goal in the second half didn't arrive until the 83rd minute as Wayne Rooney blazed a shot over from 20 yards.

Porto continued to look like the more dangerous side, and they almost found the equalizer five minutes from time as Mariano Gonzalez found Lisandro Lopez inside the box with a pass and he turned and shot at the keeper from 10 yards.

Helton kept his team alive in stoppage time with a diving stop on Ronaldo, but there were no last-minute heroics this time around and United held on for the win.