The Blues were given a harsh lesson by champions Liverpool with an authoritative performance particularly in the second half.
Chelsea started well and could have taken the lead on several occasions during the first period but Andreas Christensen was sent off for hauling Sadio Mane to the ground on the stroke of halftime.
Liverpool came out flying after the break as Mane headed home a Roberto Firmino cross on the 50th minute mark to put the visitors ahead.
The Senegal superstar got his second of the game four minutes later when he chased down Kepa Arrizabalaga’s casual pass to tap home.
This was only the third time that Chelsea lost their first home match of a Premier League season, also doing so against Blackburn in 1993-94 and Burnley in 2017-18.
Speaking to the media after the game, Lampard insisted he was happy with his side’s attitude in the game.
“We showed moments on the counter-attack when we were dangerous in the first half,” the former Derby County manager said.
“My team talk was be more confident on the ball then the red card changes the whole team talk."
"I am happier in many ways than after Brighton. I saw spirit and desire to defend, the midfield giving everything. Players should take heart, it's how we go forward from now.
"With new faces we have got a month or so in pre-season. With the way we defended, I am very happy. We have to have time. Our process starts here. Our objectives and expectations are higher, but I saw a lot of character and spirit."