City, who left striker Sergio Aguero and goalkeeper Claudio Bravo on the bench, led when Kevin de Bruyne played a one-two with Jesus before stroking home.

Four minutes later, they doubled their lead when the impressive Leroy Sane beat two defenders and his deflected cross was tapped home by David Silva.

And the game was as good as won before half-time when Raheem Sterling squared the ball to Jesus to tap home.

Yaya Toure added a fourth after the break from a penalty when Hammers debutant Jose Fonte brought down Sterling.

West Ham, who made errors to lose possession for each of City's three first-half goals, have been beaten heavily by City twice at home in 2017, having lost 5-0 in their FA Cup meeting last month.

City are now only behind fourth-placed Liverpool on goal difference, 10 points behind leaders Chelsea.

City boss Pep Guardiola revealed before the game that he had decided to stick with goalkeeper Willy Caballero and his front three of Sterling, Sane and Jesus - all of whom started Saturday's 3-0 win over Crystal Palace in the FA Cup.

And it worked in sensational style the trio - aged 22, 21 and 19 respectively - ripped the Hammers to shreds.

Jesus, making his first Premier League start following his £27m move from Palmeiras this month, assisted the opener as City broke from their own half at speed with De Bruyne. The Brazilian exchanged passes before the Belgian, who was also impressive throughout, guided the ball past Darren Randolph.

The second goal was made by Sane, who has recently hit form following a slow start after his £37m summer move from Schalke, with the German skinning two Hammers defenders and crossing, via a touch from Randolph, for Silva to tap home.

The dynamic front three all had a hand in the third, with Sane playing in Sterling, who passed the ball across goal for a Jesus tap-in.

Their second-half performance was still dominant albeit less sensational, perhaps because it did not need to be, but they got their fourth when Sterling was brought down by Fonte and Toure narrowly beat Randolph.

In goal, Caballero kept his third clean sheet of 2017, having only played three matches, in contrast to the benched Bravo, who had conceded the last six shots on target he had faced.

West Ham have now conceded 12 goals to City this season, including nine in 2017 - all at London Stadium.

And while City were brilliant, the Hammers played a huge part in their own downfall.

Aaron Cresswell gifted the ball to City for their first, then lost a 50-50 before the second goal and Pedro Obiang gave the ball to Sane for the third. Centre-back Fonte marked his debut, following his £8m move from Southampton, by conceding a penalty for Toure's second-half penalty.

They only forced Caballero to save the ball once - a simple fourth-minute stop from Michail Antonio.

Slaven Bilic's side - who only had 30% possession - did have the ball in the net once, although Antonio was offside when he latched on to debutant Robert Snodgrass's through ball to fire home.

Manchester City boss Pep Guardiola to BBC Sport: "Our high pressing was good. We were so aggressive without the ball.

"Gabriel Jesus is a fighter with instinct for the goal. He's good at assists too.

"We played a front three with an average age of 20. I like the fans to be excited. Those players are the future of the club. Leroy Sane had some problems at the beginning but now he's settled. They will be important players for the next few years."

West Ham boss Slaven Bilic told BBC Sport: "It's like a copy and paste from the FA Cup game. It's very frustrating. We made such mistakes for the first and third goal. If you give the ball away in those areas, they'll punish you.

"When it's 3-0, it's hard to play against them. You are hoping if you score you can turn a game around. But at 3-0 it's more likely you'll concede more as they'll gain confidence.

"It's a heavy defeat for us but we can't let it hurt us a lot. We have to bounce back like we did after the FA Cup defeat."

Analysis - 'City will be found out'

Former Chelsea and Everton winger Pat Nevin, BBC Radio 5 live

"I think if Manchester City play the team they did tonight away from home against other team, they will be found out.

"They are far too open. Yaya Toure, as the holding midfielder, won't get around enough against decent teams.

"West Ham are the perfect team for Manchester City. They played 4-4-2 and were destroyed in midfield.

"Tactically it was a mess."

(BBC)