Pep Guardiola’s side will take on the German champions with the reward a semi-final berth against either Real Madrid or Chelsea.
“They’re very strong of course,” said Begiristain.
“Bayern are one of the candidates with us and you can see what they have done, they beat one of the other contenders in Paris Saint-Germain.
“They are a very strong team, very solid. It’s going to be very difficult, but also I guess we’ll also be difficult for them.
“Any time, it’s going to be a tough and wonderful game. Two good coaches, a lot of good players on the pitch and the proposals of both coaches and clubs are good ones.
“I can see a big show of great football. We’re okay. We’re fighting in all competitions and ready to go for them.
“I think in the last games we’ve been solid and created chances.
“We’re in a good mood, but the only thing is of course the opponents are there, so it’s a big one. We’re ready for the fight.
“We hope [we can reach the semi-finals], we’re confident, we want to get that consistency in this competition too, so we have to go through.
“We always respect Bayern Munich”.