The 20-year-old scored after dispossessing Foxes midfielder Wilfred Ndidi on the edge of the box before slotting past Kasper Schmeichel, despite Ndidi’s desperate attempts to rectify his error.
It was a welcome sight for the Chelsea faithful, after Blues lost their opening game of the season 4-0 to Manchester United at Old Trafford.
With his goal, the England Under-21 international became the first English-born player to score a goal for the Blues under an English manager since 1996.
Dennis Wise was the scorer on that occasion with former England manager Glenn Hoddle in the dugout at Stamford Bridge.
Since Hoddle left the club soon after Wise’s goal, three English managers have taken the reins in west London, but all on a temporary basis.
Graham Rix was in charge for two games in 2000, with Ray Wilkins and Steve Holland each managing for one game, in 2009 and 2015 respectively.
Mount, who was born in 1999, achieved another feat not seen in his lifetime.
1996 – Mason Mount is the first English player to score for Chelsea under an English manager since Dennis Wise under Glenn Hoddle against Blackburn in May 1996. Scafell. pic.twitter.com/fv3QKvDV6t— OptaJoe (@OptaJoe) August 18, 2019
The academy product is the first English player to score in his first appearance in front of the Chelsea faithful since Paul Hughes in January 1997, according to Opta.
Mount will hope his goal is the first of many, but Hughes only managed one more for the club, and was loaned to Stockport County at the beginning of the next season.
Mount played last season for Lampard too, for Derby County in the Championship while on-loan from Chelsea.
He scored on his debut for the Rams last year and has now done the same on his home debut in the Premier League.
Mount made his Premier League debut at Old Trafford, playing all 90 minutes in a chastening defeat and then came off the bench in the Blues game against Liverpool in the European Super Cup on Wednesday.
He scored his penalty in the shoot-out in that game, after the two teams could not be separated, the game ending 2-2 after extra time.
The Blues lost the shoot-out as fellow youngster Tammy Abraham’s miss from 12 yards handed the trophy to the Mersyside outfit.
And Sunday would prove disappointing for Chelsea as well, with Ndidi making up for his earlier mistake with a second-half equaliser, leaving the Blues to settle for a 1-1 draw.