Conor Gallagher spent last season on loan at Crystal Palace.

Edouard Mendy made a mistake for West Ham's goal.

Edson Alvarez was linked with a move to Chelsea on the final day of the transfer window.

The Frenchman performed well on his first appearance for the club.

Kai Havertz scored the winner against the Hammers.

Both have arrived as new defensive options for Chelsea this summer.

Edouard Mendy made a mistake for West Ham's goal.

The striker signed for Chelsea on Deadline Day.

Ben Chilwell came off the bench to score and assist against West Ham.

Ben Chilwell came off the bench to help Chelsea win all three points.

Chelsea won all three points late on against West Ham.

Kai Havertz netted a late winner for Chelsea.

Christian Pulisic faced an uncertain future this summer but has remained at the Blues.

Denis Zakaria has joined the Blues on Deadline Day.

Chelsea need to get back to winning ways.

Chelsea suffered a disappointing loss to Southampton on Tuesday night.