The boss made seven changes to his starting line-up against the Danes and was able to bring on two Academy players in the second-half to further rest some of his squad ahead of Sunday’s trip to Anfield.
“I played against Luton in the FA Cup and was not thinking about United,” said Guardiola.
“I played today and needed energy, fresh legs.
“I know how tired and exhausted some players were today to play three days after United.
“Normally in the Champions League when you play Wednesday in all the countries in the world - except in this country - they allow you to play on Saturday. We played on Sunday.
“So I needed fresh legs. People who could sustain. We were fortunate, lucky to score two early.
“That helped us a lot because this competition is so tricky, so dangerous.
“And we spoke and said be calm, don’t lose your emotions and if we scored one goal, two goals, the knockout will be closer.
“We scored two goals and that helped us a lot. I said to the players after the game, ‘I would not convince you, I am going to tell you we went through against such a difficult team’.
“Copenhagen played United, Bayern Munich and Galatasaray. They are a difficult opponent.
“So well organised. And, of course, to be part of the titles we need everyone.
“That’s why we used [our squad]. Really pleased with the performance. The people expect a lot of things, but I know how difficult it is.
“For another year we are in the best eight teams in Europe.
“The draw, next Friday, we will be there. Incredibly happy we are still in all competitions.”
The boss also praised the Club’s Academy graduates, with Oscar Bobb and Rico Lewis playing the full 90 minutes and Micah Hamilton and Jacob Wright among the second-half subs.
“It’s a process,” he said.
“Rico played better in the last 10, 15 minutes in the second half. Oscar played really, really good the first minutes and after he lost the ball in transitions - and they scored a goal - he dropped a little bit, his mood.
“But they are so young. Now they’ve had 90 minutes, Oscar, for the next game will be more aware that he can do it.
“That’s the process to do it. We need him. We had injuries with Jeremy and Jack. That’s why we need players fresh.
“Of course in all teams there are players who play more than others. But we will need him.
“I know how Phil runs against United. Bernardo. When I spoke to them, I saw many things, ‘Oh Pep, I’m so tired’. At Luton, Phil didn’t play. Ruben didn’t play.
“Other players didn’t play. It was Luton and I know how the people struggle there. We won 1-2, suffering the last 10 minutes. We were under the post.
“So I know how difficult it was. I have done it in the past. Everyone makes a contribution.”
