Danny Welbeck put the visitors ahead in the 20th minute, heading in a corner but Cristiano Ronaldo responded in the 31st minute with a magnificent header of his own.
In the 33rd minute Danny Welbeck nearly got his second goal of the game as he just missed re-directing a cross from Robin Van Persie past Diego Lopez. Instead, Welbeck's missed the attempt and Lopez was able to deflect the ball out for a corner. Welbeck decided to go after the ball with a high boot rather than a diving header and it might have made the difference. Wayne Rooney had a great chance on the subsequent corner, sending his shot from the top of the box just side of the goal.
David De Gea made a beautiful save in the 38th minute denying a close range snap shot from Mesut Özil. The German midfielder had gotten behind the United defense and brought down a lovely long ball from Xabi Alonso. Despite having to fight the ball a bit to settle it, Özil was still able to get off a great shot. Credit for De Gea for making an excellent reflex save.
Özil inexplicably passed up a shot attempt a minute later as he stood wide open on the right side of the box. Instead of testing De Gea again, he centered the ball towards Ronaldo but the Portuguese striker was unable to get to the ball and it was clumsily cleared at last by United.
Real Madrid wanted a penalty called in the 40th minute when Phil Jones knocked down Ángel Di María with some hard shoulder-to-shoulder contact after Di Maria has weaved his way through the United defense. The referee was right on the spot and didn't hesitate in waving away the protest. It seemed like an obvious penalty to me, but I have the advantage of slow motion replay.
Real Madrid will be happy with 99% of the first half but that 1%, a momentary lapse on a corner that allowed Danny Welbeck to score, is a big one. Plenty of time to build up a lead before heading to Manchester for the second leg though.