Champions League: Bayern, Barca reach semifinals

Bayern Munich's Robert Lewandowski scores their fifth goal during their Champions League quarterfinal second leg match against Porto at the Allianz Arena in Munich, April 21, 2015. [Photo/Agencies]

Spaniard Thiago made their dominance count four minutes later, heading in at the near post from a Juan Bernat cross to to give them the lead on the night.

With the home fans urging their team on, Jerome Boateng got the second in the 22nd, rising high to bury another header as the visitors' defence struggled to contain Bayern on the wings.

Although a 2-0 scoreline would have been enough to send them through on away goals, Bayern did not let up and Lewandowski drilled home a header in the 27th as Bayern ripped Porto's rearguard to shreds.

Mueller's deflected shot in the 36th made it 4-0 before Lewandowski grabbed his second four minutes later.

Bayern took their foot off the gas after the break and Jackson Martinez pulled one back for the visitors in the 73rd before they were reduced to 10 men when Marcano got a second yellow card for a rash challenge on Thiago.

Bayern put the icing on the cake with their sixth goal in the 88th minute as they preserved Spaniard Guardiola's impressive record of never having a team eliminated at the Champions League quarter-final stage.