Manchester: The People's Club welcomed back its fans and Chelsea felt the full force.
With 2,000 supporters allowed back into Goodison Park after nine months, Everton won 1-0 on Saturday to end Chelsea's 17-match unbeaten run in all competitions.
It means third-place Chelsea can be overtaken if Leicester beats Brighton on Sunday and front-runners Tottenham and Liverpool can pull further away at the top of the Premier League.
"I don't think we were at our best, Chelsea manager Frank Lampard said.
"We have been on a really good run and we knew what was coming with Everton physically and we didn't handle that well. We didn't show enough to break them down."
It was an uncharacteristic mistake by Chelsea goalkeeper Edouard Mendy - bringing down Dominic Calvert-Lewin that allowed Gylfi Sigurdsson to score a penalty in the 22nd minute and spark home celebrations as Everton rose to seventh.
"The impact was really strong we were really pleased," Everton manager Carlo Ancelotti said.
"It is really important to have support. It's a totally different environment, completely."
Read More| Angulo on target as Goa push Odisha into further misery
And totally different about 30 miles (48 kilometres) away in Manchester, which remains in a higher level of coronavirus restrictions so no supporters were allowed into the city's derby match for the first time.
There was no atmosphere, no intensity and no goals as Manchester United and Manchester City drew 0-0 in the 183rd derby.
The rivals are both unusually low in the Premier League, too. United is eighth and City, which has won the league three times since its neighbour last lifted the trophy in 2013, is a point and place behind.
"We're not happy to draw 0-0 at home at Old Trafford," United captain Harry Maguire said, "and not create any big chances for fans to get off their seats and get excited about."