Pep: Bayern must attack Arsenal at Allianz
The Bundesliga leaders enter the second leg as huge favourites to progress after a 2-0 win in London three weeks ago, but the former Barcelona coach is taking nothing for granted and knows Arsenal have players who can hurt his side.
After a 3-1 first leg win at Arsenal in the same round of the competition last season, Arsene Wenger's men came within a whisker of springing a shock, triumphing 2-0 at the Allianz Arena - only to go out on away goals.
Guardiola believes Bayern's best form of defence will be to attack, and has called for his players to dominate possession when Arsenal visit on Tuesday, having confessed a dissatisfaction at their overall performance against Wolfsburg on Saturday, despite winning 6-1.
"If we let Arsenal keep the ball, we will have a lot of problems," he said.
"They have a lot of quality, every single player has unbelievable technical skills with the ball - it doesn't matter if you are aggressive or not.
"They have players like (Santi) Cazorla, (Mesut) Ozil, (Tomas) Rosicky, (Mikel) Arteta - it is no problem for them to keep the ball in their lines.
"So the only way to avoid that is to keep the ball for ourselves - and obviously we have to be aggressive. What I noticed about my team was that we are only good when we just think about attacking.
"If we start to speculate and think about what we may have done wrong in London, then they have a good chance to win and we won't go through to the quarter-final.
"I know Arsenal very well, I played two times against them with Barcelona. I know their coach.
"If we have the ball, we will be in the next round. If Arsenal have the ball, they will be in the quarter-final."