Bayern appointed Heynckes, 72, as interim coach until the end of the season following Carlo Ancelotti's dismissal the day after a 3-0 Champions League group-stage defeat at Paris Saint-Germain.

"When I started, nobody believed Bayern Munich would reach the Champions League semifinals," Heynckes told a news conference.

"My players have lofty ambitions in the Champions League to go all the way to the final. I think we are in a good place at the moment, but you need some luck, good officials and your best form on the day."

Sevilla proved resolute opponents in a feisty affair in Munich. Joaquin Correa rattled the crossbar with a header on the hour mark, before receiving a red card in added time for a late challenge on Javi Martinez -- with a melee ensuing after the robust tackle on the sidelines.

"Sevilla were tactically good and you could see why they knocked out Manchester United in the last round. We were also lucky with the header that hit the crossbar [Correa]," Heynckes said.

"Top sides have already exited the competitions -- shocks happen time and time again. We saw yesterday in Rome that you cannot afford to underestimate any side in the Champions League. Barcelona travelled to Rome and thought it would be easy. See how that turned out?

"But we had our chances too on the night and didn't get nervous despite failing to score like we normally do. Over the two legs, we were deserved winners with the goalless draw enough after winning the first leg 2-1 away," he added.

Heynckes said keeping a clean sheet in the match was paramount to his team progressing and added he made that clear to the players before the second leg.

"We showed fight with our performance today," he said. "I'm very happy that we didn't concede because that's something I demanded from my team. You have to keep a clean sheet in games like this.

"The goalless draw was enough for us to go through today. We didn't let ourselves get flustered and become nervous.

"Sevilla had some good moments, but sometimes you just need to keep a clean sheet. That's what I told the players and that was enough tonight.''

Ahead of Friday's semifinal draw with holders Real Madrid, Jurgen Klopp's Liverpool and Roma potential opponents, Heynckes said: "I don't have any preference for the draw -- any semifinal will be difficult against three top opponents."

Sevilla boss Vincenzo Montella knew Correa's header hitting the bar was a pivotal moment.

He said in his postmatch press conference: "We have fallen proudly.

"The team played a good game throughout, we played with balance and we had our chances, not very clear ones, but if there was a goal in the second half from the head of Correa....

"The team have played with spirit and personality.

"It was not easy, our opponents can compete to win the Champions League. We had bad luck with two goals at home and today with the crossbar, football is like that and we have to accept it.''