There was to be no instant response following the midweek debacle against Porto, as Jose Mourinho's charges were outplayed in the second half to continue their poor league start.
Chelsea's miserable 2015-16 season continued as it fell to a stunning 3-1 defeat against a rampant Southampton side at Stamford Bridge on Saturday.
The host took the lead through Willian's free kick, but Steven Davis deservedly leveled proceedings just before halftime.
Chelsea thought it should have had a penalty when Radamel Falcao was brought down by Maarten Stekelenburg in the second half shortly before Sadio Mane put the Saints in front after a mistake from the returning John Terry.