A second-half goal from Iniesta completed victory for Pep Guardiola's men, who became the first team to reach five consecutive semifinals in the competition since the great Real Madrid side of the late 1950s.
"You have to play the perfect game to win here and unfortunately we made some mistakes, both in defence and in attack," said Milan coach Massimiliano Allegri.
Having seen his side win 2-0 at Stade Velodrome last week, Bayern coach Jupp Heynckes elected to start with Arjen Robben and top scorer Mario Gomez on the bench at Munich's Allianz Arena, which will host the final on May 19. Gomez's replacement, Ivica Olic, took full advantage of the opportunity to shine, converting low crosses from Franck Ribery and David Alaba to put Bayern 2-0 up by the interval.
"We were very concentrated, despite the amount of games we are playing at the moment," said Heynckes, who is attempting to guide his side to a treble of trophies in the Champions League, Bundesliga and German Cup. "Marseille weren't in the quarter-finals for nothing and they tried everything."
Suspended for the first leg, Marseille goalkeeper Steve Mandanda kept the scoreline respectable thereafter but OM have now gone 10 games without a win.
"We lost to a great team, but we did not give up," said striker Loic Remy. "Hats off to Bayern, I hope they go all the way. We still have the League Cup final [against Lyon on April 14] to look forward to and we want to do well in the league."
Bayern will play either Real Madrid or Cypriot representatives APOEL in the last four, with Madrid carrying a 3-0 lead into the second leg.
- AAP