Yet, as an opposition manager and even in narrow defeat, he will have purred at the performance delivered by his Derby County team in surroundings so familiar.
Ahead of kickoff, banners with the words "GOAL AFTER GOAL, GAME AFTER GAME" and "FOREVER A BLUE, ALWAYS A LEGEND" flanked a giant image of Lampard in the Matthew Harding Stand, emblazoned with the number 211 - his peerless goal tally for Chelsea.
Lampard gave everything to Chelsea and they gave it back, in recognition of a career that yielded 211 goals in 648 appearances, saw him lift 11 major honours and nearly win the Ballon d'Or, coming second to Ronaldinho back in 2005.
Still, the visitor was just as unsafe going forward as it was in its own box and snatched a second equaliser after 27 minutes, Mount squaring for a Waghorn tap-in.
A full 21 minutes had passed before the next goal flew in, with a fluffed clearance once again leading a Derby defender, namely Richard Keogh, to put through his own net in embarrassing fashion...
And after being given special permission to play against their parent club, Mount and Tomori would have been hoping to impress. Lampard's new side had his old side absolutely rattled for long periods here, with Mason Mount and Tom Huddlestone outstanding. This was not how he had envisaged scoring his first Chelsea goal in front of the Shed End.
Lampard took it all in his stride, of course, transitioning effortlessly from clapping the songs directed at him to vigorously applauding his Derby players as they hassled and harried Chelsea into defensive mistakes.
Incredibly, the links to Chelsea don't quite end there; the unfortunate goalscorer was one of the club's players out on loan with Lampard's club, Fikayo Tomori. If this was an audition for Lampard as a future manager at Stamford Bridge, then he can't have done his chances any harm.
Chelsea have won 11 of their past 12 home League Cup games against sides from outside of the Premier League, drawing the other 1-1 with Burnley in November 2008 before being eliminated on penalties.
Marriott has been directly involved in six goals in his past five games for Derby in all competitions (four goals, two assists).
At 2-2 before the half-hour mark, the Rams' visiting fans were in fine voice but they were silenced once more just before half-time when Cesc Fabregas scored what would turn out to be the winning goal.
Chelsea are still unbeaten in competitive games this season.