Arsenal's hopes of reaching the Champions League knockout phase were left hanging by a thread on Wednesday after they were thrashed 5-1 by Bayern Munich, while Chelsea revived their faltering campaign with a nervy 2-1 victory over Dynamo Kiev.
Zenit St Petersburg became the third team to reach the last 16 of the competition as the Russian champions maintained their 100 per cent record with a 2-0 win at Lyon, while Barcelona edged closer towards qualification after strolling past BATE Borisov 3-0.
Bayern's unbeaten start to the season was ended by a 2-0 defeat at Arsenal a fortnight ago but Pep Guardiola's side exacted revenge and then some at the Allianz Arena.
Robert Lewandowski headed Bayern into a 10th-minute lead as Arsenal's attempt to catch the Poland striker offside backfired.
Thomas Mueller added a second just before the half hour as his shot deflected off Per Mertesacker and crept in at Petr Cech's near post.
David Alaba effectively put the game beyond reach just before the break as the Austrian curled home a third after stealing the ball from Santi Cazorla on the edge of the area.
Substitute Arjen Robben then smashed home an Alaba cutback early in the second half while Olivier Giroud's acrobatic effort pulled one back for the Gunners.
But Mueller compounded Arsenal's misery a minute from time to condemn the Gunners to their joint-heaviest European defeat, equalling the 4-0 drubbing at AC Milan in the last 16 of the 2011/12 edition.
A chastening evening for the Londoners was made all the more damaging as Olympiakos recovered from a goal down to beat Dinamo Zagreb 2-1, leaving Arsenal six points behind the Greeks, and Bayern, with two games to play.