Serge Gnabry's double and Robert Lewandowski's goal in the last-16 first leg all but ended Chelsea's chances of making the quarter-finals of Europe's premier club competition this season.
It was the Blues' heaviest home defeat in the Champions League, and it could have been worse:
Lewandowski's goal in the 76th minute summed up Chelsea's night as four Blues players were left for dead by the superb Alphonso Davies in the build-up:
Lampard made no excuses after a chastening 90 minutes for his Chelsea side, per BT Sport (h/t MailOnline's Daniel Matthews):
"That's football at this level. The levels of Bayern Munich were fantastic. ... It was a harsh lesson of reality for the players. If you go for 90 minutes you have to show more than we showed. ... [The players] need to use this to a positive effect. It might not feel like that this evening, but they need to understand the levels in the Champions League when you reach the knockout stages. They outclassed us in pretty much every department, so it was quite sobering."
Lampard, who was part of the Chelsea side that shocked Bayern to win the 2012 Champions League final, added that he would "never say the door is closed" on making the quarter-finals:
But the Blues will need a performance better than anything they have shown this season if they are to overturn the deficit in the return leg on March 18, not least as Jorginho and Marcos Alonso will miss the game due to suspension.
Perhaps more concerning for Lampard and Chelsea is how they respond to such a chastening loss when they return to Premier League action at Bournemouth on Saturday.
The Blues have won just five of their last 15 games in the English top flight and are only clinging on to fourth spot in the table due to the inconsistencies of the clubs below them:
It will take a miracle for Chelsea's Champions League campaign to continue beyond the last-16 second leg this season.
But they still have control over whether they return to the tournament next season. They could be aided in their task by the fact fifth place may secure Champions League qualification after Manchester City's two-year UEFA ban.
Chelsea need to find some consistency quickly, though, because a couple more poor results could see them drop as low as eighth depending on how their competitors fare.