The Red Devils took the lead in the 18th minute when Marcus Rashford expertly converted his penalty.
Anthony Martial then made it 2-0 in the 65th minute when he fired home from close range, and Rashford made it three just two minutes later with a cool finish.
Summer signing and second-half substitute Daniel James then made it 4-0 to the hosts when he converted from close range albeit thanks to a deflection off Emerson.
It was a miserable day for Frank Lampard and his Chelsea FC side, who failed to click into gear during their Premier League opener.
But it marked a fantastic start to the season for Manchester United, with all three summer signings producing positive performances.
And former Red Devils boss Ferguson clearly liked what he was seeing as he watched on from the stands at Old Trafford.
Manchester United, whose win moved them up to second place in the table, will return to Premier League action on Monday 19 August when they travel to Wolves.
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