Chelsea recorded their biggest away Premier League win since October 2018, ironically at Burnley too, by beating Sean Dyche’s side 4-0.
Reece James, starting his first game since December, opened the scoring two minutes after the interval, drilling a shot into the far, bottom corner after turning Dwight McNeil inside out.
Havertz then pulled away from his marker Connor Roberts to head home a nicely floated cross from Christian Pulisic to make it 2-0 for the visitors.
The German then had another simple finish, converting a James cross from close range, and Pulisic had the easiest of tasks scoring after Burnley defender James Tarkowski diverted a Saul Niguez cross into his path.
Chelsea are third on 53 points, 13 points behind leaders Manchester City while Burnley stay in 18th place on 21 points