Jose Mourinho suffered a 1-0 defeat at Everton as birthday boy Steven Naismith celebrated his first league start of the season in perfect fashion.
The Scotland international, who scored in the 2-1 defeat at Stamford Bridge on the final day of the season when he was last in a Premier League starting line-up, headed home the winner in first-half added time.
His goal also kick-started the Roberto Martinez era at Goodison Park after three successive draws had left the Spaniard with some convincing still to do.
Chelsea have hardly been pulling up trees like they did in Mourinho's first spell in charge in 2004.
Back then he began with four successive wins and did not taste defeat until his ninth outing in the league.
This time around it appears he is not so special with two victories, a draw and now this defeat.
The much-anticipated Premier League debut of Chelsea striker Samuel Eto'o did not go to plan for the 32-year-old, who was outshone by Gareth Barry making his first appearance for the Toffees after his deadline-day loan move from Manchester City.
His class is not in doubt but the former Barcelona and Inter Milan forward may be a bit rusty after a money-spinning spell in Russia with Anzhi Makhachkala.
It certainly looked that way when he headed wide Ramires' cross after five minutes when he should have - at the very least - hit the target.
More embarrassingly the Cameroonian then ballooned a long-range shot into the upper tier of the Gwladys Street end.