Havertz has endured a disappointing first season following his £70 million ($96 million) move from Bayer Leverkusen last year.

But the Germany midfielder was given a rare start by Chelsea boss Thomas Tuchel and he responded by playing the key role in both goals at Stamford Bridge.

Havertz's shot was deflected into the Everton net for a Ben Godfrey own goal in the first half.

The 21-year-old hasn't scored in the league since October, but Tuchel entrusted him with an important role as Chelsea's false nine and his intelligent movement put him in position to earn the second-half penalty that Jorginho converted.

Chelsea are now four points clear of fifth-placed Everton, although West Ham would close the gap to two points if they beat Leeds later on Monday.

The west Londoners are unbeaten in 11 games in all competitions -- winning eight times --- since Tuchel replaced the sacked Frank Lampard in January.

Their renaissance under Tuchel is a credit to the former Paris Saint-Germain boss, who is the first manager to see his side keep a clean sheet in each of his opening five home Premier League games.

On current form, Chelsea look a good bet to qualify for next season's Champions League via a top-four finish, while they still have aspirations to win this season's competition after beating Atletico Madrid 1-0 in the last 16 first leg.

Everton's first away league defeat since November was a significant blow to their hopes of top-four place.

Tuchel made five changes from the 1-0 win against Liverpool last Thursday as Havertz and Callum Hudson-Odoi came in.

Making way for Havertz was Mason Mount, whose superb performance and clinical finish had inspired the victory at Anfield.

But Tuchel's tinkering didn't unsettle Chelsea and they dominated possession from start to finish.

- Revitalised Havertz-

Jorginho twice fired narrowly wide in the opening exchanges and Chelsea's pressure was rewarded with a stroke of luck in the 31st minute.

Hudson-Odoi made a purposeful burst in from the left and picked out Marcos Alonso's run into the Everton area.

Alonso swiftly whipped a cross towards Havertz and his volley took a wicked deflection off Godfrey as it flashed past wrong-footed Everton keeper Jordan Pickford.

Sweeping forward from the left wing-back position again, Alonso eluded the Everton offside trap, but this time his shot was well saved by Pickford.

Pickford had to tip over Alonso's swerving free-kick when it threatened to catch him out at the near post early in the second half.

The revitalised Havertz turned to fire past Pickford moments later, only to see the goal disallowed by VAR after he controlled the ball with his arm.

Everton barely troubled Chelsea goalkeeper Edouard Mendy for nearly an hour and even when Richarlison had a clear sight of goal, the Brazilian slipped and miscued his shot wide.

Tuchel's men kept coming in waves and Reece James blasted just wide from long range before Hudson-Odoi saw his curling effort pushed over by Pickford.

A second goal looked inevitable and it duly arrived in the 65th minute.

Havertz was clattered by Pickford and Jorginho dispatched the penalty with his customary hop step.

Chelsea could easily have won by more, but Timo Werner and Mount were denied by Pickford as the hosts threatened to run riot.

Ben Godfrey

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