Goals from Leroy Sane, Serge Gnabry, Harry Kane and Mathys Tel gave Bayern a 4-3 win over Manchester United.
United, for whom Rasmus Hojlund scored his first goal, looked sharp in attack, but poor defending and goalkeeping cost them once again.
United started well and ought to have taken the lead early on, but Alphonso Davies made a fine tackle on Facundo Pellistri before Sven Ulreich saved Christian Eriksen’s subsequent shot.
Then, on 28 minutes, Bayern took the lead, Sane playing into Kane, accepting a fine return, and slapping a tame effort over which Andre Onana somehow dived before, shortly afterwards, the brilliance of Jamal Musiala allowed Serge Gnabry to make it 2-0.
After the break United again started well, pulling a goal back on 49 minutes when Rasmus Hojlund somehow recorded his first goal for the club with the aid of two deflections.
But within minutes, Bayern won the penalty which made the game safe, Eriksen adjudged to have handled Dayot Upamecano’s header.
From the penalty spot, Kane made no mistake, and though Casemiro bagged two late goals to make things interesting Tel’s terrific finish in between gave the German champions control of the group, while United desperately need a break.