Nicolas Jackson tapped home into an empty net to make it 4-0 to Chelsea immediately after the interval.
After a disastrous season by their standards, the Blues are trying to finish it with a bang as they demolish London rivals West Ham at home.
Cole Palmer broke the deadlock before goals from Conor Gallagher and Noni Madueke made it 3-0 just before the break.
Chelsea immediately got back to it after half-time as Jackson grabbed his first goal of the game, rolling the ball into an empty net after a quick break.
Video courtesy of Bein Sports.