After victory over Borussia Monchengladbach, he made a point of explaining why he wants the booing of the anthem to stop and why he hopes this performance will convince the stay away supporters to return.
"Our fans, they have to know we play for them," said Guardiola. "It is our job, we are here but without fans there is no reason why we are here. Our fans have to know we need them in the Champion League. In the Premier League everyone comes here but in the Champions League they don't.
"We need them to compete against the best teams in the world. With our supporters and their songs, we are stronger.
"I think these players have done from the beginning, our players deserve the stadium completely full. Hopefully against Barcelona and Celtic it will happen and if you are able to go to the next stage. I think today it is a good moment to enjoy our football with the fans."
He continued: "I was not here what happened but they must forget what happened in the past. What only we can do is play every time better and people say I spend 90 minutes there and I have fun.
"Today the stadium is not completely full so the only thing we can do is play good so the people at home say wow next time I will be there. We have to be so proud to play in this competition. In the next three or four weeks, the best football player ever (Lionel Messi) is coming.
"The next step with this club is to be there every single season, quarter final, semi-final and maybe in the final. It is not the point to arrive once and after disappear."