Frank Lampard suffered the heaviest defeat by a Chelsea manager in his first match in charge since Danny Blanchflower lost 7-2 to Middlesbrough in December 1978.
For a second consecutive season, Manchester United’s first goal of their Premier League campaign has been a penalty (also Paul Pogba v Leicester City in 2018-19).
Chelsea will end the day in the Premier League relegation-zone for the first time since 30 September 2000.
Since his debut in September 2015, Anthony Martial has scored 49 goals in all competitions for Manchester United – more than any other player.
The last manager before Frank Lampard to lose by four or more goals in his first Premier League match in charge was Gustavo Poyet in October 2013 (Swansea City 4-0 Sunderland).
Chelsea’s starting XI average age was 25 years and 199 days – compared to Manchester United’s average age of 24 years and 227 days.
United have a full week to prepare for the game at Wolves on 19 August (20:00 BST). Before then, Chelsea play two games – the Uefa Super Cup against Liverpool in Instanbul on Wednesday and a home league game with Leicester next Sunday .