Nicolas Jackson fired Chelsea to a 3-0 win against West Ham as the Senegal striker repaid his manager's faith with a decisive double at the London Stadium on Saturday.

Jackson struck twice in the first half before Cole Palmer wrapped up Chelsea's third win in five Premier League games under new boss Enzo Maresca.

It was a well-timed brace from Jackson, who was Chelsea's first choice striker by Maresca on Friday, despite Christopher Nkunku's match-winning impact against Bournemouth last weekend.

Although Jackson signed a contract extension earlier in September that will keep the Senegal star at Stamford Bridge until 2033, there were calls for Nkunku to start after the French forward came off the bench to net in the 1-0 win at Bournemouth.

Jackson scored 17 goals in an inconsistent debut season with the Blues and was guilty of missing a number of big chances.

But the 23-year-old has been in fine form at the start of this season and already has four goals in six games in all competitions.

"We are completely 100 percent happy with Nicolas. He is working hard since I arrived, he's very good on the ball in terms of numbers," Maresca said.

Chelsea have won all three away league games this season, losing only once, against champions Manchester City, in their five top-flight matches.

Despite a reported power struggle between Chelsea co-owners Todd Boehly and Behdad Eghbali behind the scenes, former Leicester boss Maresca, who replaced Mauricio Pochettino in the close-season, has made a strong first impression.

After disappointing sixth and 12th place finishes in the last two seasons, there are encouraging signs that the Italian could be the manager to turn Chelsea's expensively assembled squad of underachievers into top four contenders.

"The points are important, but in this moment the most important thing is the way we progress," Maresca said.

"We are in the right direction, but many things we can do better. It is a process and we are learning."

The Hammers' dismal start to the season has already put new boss Julen Lopetegui under pressure, with the former Spain and Real Madrid boss jeered by the few frustrated fans who hadn't fled the ground well before the final whistle.

West Ham have won just one of their five Premier League games this term, losing three in a row at home to start a league campaign for the first time.

"It's a bad day for sure," Lopetegui said. "There is no excuse. We have to be honest and know that we need to improve."

- Rampant Chelsea -

Chelsea made a flying start after just four minutes when West Ham switched off at a free-kick, allowed Jackson to take Jadon Sancho's pass and surge down the right flank.

Jackson cut into the penalty area and beat Alphonse Areola's weak attempted save with ease.

Jackson was proving impossible for West Ham to subdue and he teed up Cole Palmer for a low strike that flashed just wide.

Chelsea's pressure was relentless and there was a sense of inevitability about their second goal in the 18th minute.

At the climax of a free-flowing move, Moises Caicedo produced a deft pass that pierced the West Ham defence, allowing Jackson to guide a composed finished past Areola.

Making his first league start for West Ham after his close-season move from Leeds, Crysencio Summerville demanded a penalty after Wesley Fofana's tug sent him sprawling, but VAR rejected the forward's appeals.

Lopetegui was furious with West Ham's lethargy and responded by hauling off Argentina midfielder Guido Rodríguez before half-time.

But Rodriguez's replacement Thomas Soucek hardy improved Lopetegui's mood when he wastefully fired straight at Chelsea keeper Robert Sanchez.

Sancho looked revitalised following his loan from Manchester United, causing problems with his nimble dribbling in his first Premier League start since May 2023.

Palmer killed off West Ham in the 47th minute as the England forward took Jackson's pass and slotted past Areola from a tight angle.