There was no pre-match fanfare to present Antonio Conte to the Stamford Bridge crowd before his debut as Chelsea manager, but Monday's 2-1 Premier League win over West Ham United sent a clear message that the team are already marching to his orders.

Conte's side dominated their London rivals with the kind of drive that made his name as a player and as a coach in Italy, energy that was so lacking at Chelsea last season when the 2015 champions failed miserably to defend their title.

As the former Italy and Juventus manager watched the game from the sidelines, barking instructions and waving his arms, the home crowd sensed a renewed confidence among many of the players who performed so poorly a few months ago.

After being hugged by fans - many of whom have still to come to terms with the sacking last year of the club's most successful manager Jose Mourinho - Conte said he believed his approach was working well.

"Every manager, when (he) arrives in a new club, tries to bring his philosophy, his philosophy of football," he told reporters.

"We are working only one month with the players but I am pleased because tonight I saw the right intensity.

"It is important to bring something of different compared with last season."

After struggling to match West Ham in the opening 15 minutes, Chelsea gradually tightened their grip on the game.

Eden Hazard, booed by fans last year for failing to produce anything like his best form, got off the mark early in the second half by converting a penalty after defender Cesar Azpilicueta was fouled by Michail Antonio.

Chelsea dominated the second half with Hazard influential and new signing N'Golo Kante adding more bite in midfield.

But it looked like they would be punished for not turning their possession into goals when West Ham defender James Collins hooked in a shot in the 78th minute after the home side failed to clear a corner.

Spain striker Diego Costa, however, capped a performance that recalled his early, unstoppable form at Chelsea by slamming home a last-minute winner after new signing Michy Batshuayi, brought on by Conte minutes earlier, set him up with a header.

"I am very happy with the players because they are putting themselves in the team," Conte said.

"To have a great team, it is important this. To have a great spirit and players with a great talent to put themselves in the team."