Bayern Munich crushed Barcelona 4-0 in the first leg of its Champions League semifinal . The German side won 3-1 on aggregate and will face either Real Madrid or Atletico Madrid, who beat Roma 1-0 to reach last season's final. Bayern boss warns against complacency ahead of second leg . Barcelona 's Gerard Pique believes `` almost impossible '' for his side to progress .
Bayern Munich crushed Barcelona 4-0 in the first leg of its Champions League semifinal . Thomas Muller scored twice with Mario Gomez and Arjen Robben also on target . Bayern boss warns against complacency ahead of second leg . Barcelona 's Gerard Pique believes `` almost impossible '' for his side to progress .