Manchester - Manchester United will take a narrow advantage into the second leg of their Champions League semi-final against Arsenal after edging out the London side 1-0 at Old Trafford on Wednesday.

The holders dominated the match for long periods but in the end only had an early strike from John O'Shea to show for their superiority.

"We had so many chances in the first half but their goalkeeper played so well," United goalkeeper Edwin van der Sar said. "I think our game plan was good.

"I think the match in London will be difficult, they have one or two players to come back, perhaps Van Persie, so the match is not over."

The two sides will play the second leg at the Emirates Stadium next Tuesday.

Arsenal manager Arsene Wenger said he was confident Arsenal could turn things around in the return leg.

"They played well and they started very strong," he said. "The good thing is we didn't concede more than one. We have a good chance to reverse it at home.

"They could have scored the second. That kept us in the tie and we want to take advantage of that. We didn't create enough. But it's more important to think about what we want to do next Tuesday.

"We still believe we will do it at home and I believe we will see a different Arsenal next week."

Arsenal will also fancy their chances of progressing because they were hampered by the absence of the injured Van Persie.

Cristiano Ronaldo smashed a shot onto the crossbar midway through the second half, while Manuel Almunia had to make several excellent saves to prevent United taking a bigger lead into the second leg, especially one from Carlos Tevez early on.

United had threatened the Arsenal goal a couple of times before making the breakthrough and the only surprise was that the goal, when it did come, came through the unlikely figure of O'Shea.

Michael Carrick worked his way to the byline after a corner and his deflected cross was directed into the net by O'Shea with a fierce finish.

Ronaldo headed a good chance straight at Almunia, while Cesc Fabregas shot straight at Van der Sar in a rare Arsenal attack.

Wayne Rooney fired a shot just wide and Ronaldo then smashed a stunning effort onto the crossbar, while at the other end, Emmanuel Adebayor smashed a good effort over the bar.

United chased a second goal to give themselves more of a cushion going into the second leg but they were unable to extend their lead.

And Rio Ferdinand had to leave the pitch in the closing minutes because of injury and the defender will be assessed over the next 24 hours.

On Tuesday Chelsea drew 0-0 at Barcelona in the other semi-final first-leg encounter. (dpa)