Danny Welbeck shot straight at Manuel Neuer in the best chance of the first half at Old Trafford before Nemanja Vidic’s header gave the hosts the lead from a corner in the 58th minute.
Bastian Schweinsteiger’s superb half-volley pulled the visitors level in the 66th minute, before the Germany international saw red for a second bookable offence late on.
Manchester United has one of the best teams in the world
And Guardiola insisted that he was pleased with the result ahead of next Wednesday’s return leg in Munich.
“I am quite satisfied,” said Guardiola. “Manchester United has one of the best teams in the world.
“We scored an away goal which is important, but we also got lucky that efforts from Danny Welbeck and Wayne Rooney did not go in. The goal we conceded was difficult to defend.
“It is always dangerous when you go into the second leg with a 1-1 draw, but even a 2-1 victory would have been dangerous. We will try to win the second leg and I am sure we can do it.
“I have full confidence in my players and hope the fans in Munich will push us like the United supporters did for their team today.”
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