He remains Abramovich’s most influential appointment, the man who turned Chelsea into winners.
For the Chelsea boss, too, facing Mourinho on such a landmark occasion will feel significant, as he aims to justify Abramovich’s faith in him to emulate the glories he achieved as a player, largely under the Portuguese.
The size of Lampard’s task is only emphasised when assessing Chelsea’s success over the past 17 years.
Under Abramovich, they have won more major trophies than any other English club - 16 to Manchester United’s 14, Man City’s 11 and Liverpool’s seven. Five Premier League titles, the Champions League and five FA Cups are the biggest highlights.
Seven of those trophies were won by Mourinho, five of them in a spectacular first spell from 2004 when Lampard was one of his leading lieutenants.
Mourinho will be a physical reminder of that heavy burden of history on Sunday but if Lampard does lead Chelsea to the title in only his second season in charge, it will owe much to the 57-year-old’s influence on him - and on Chelsea, who the Portuguese transformed after joining from Porto.
The apprentice is taking on the master in a top-of-the-table clash that will offer a pointer to both men’s credentials in their bid to be champions.
Few will have a better understanding of Mourinho’s ability to forge a title-winning team than Lampard. Together they won back-to-back League crowns during the Portuguese’s first spell at Chelsea - at a time when it appeared he could do no wrong.
Mourinho arrived in England with an aura that captivated players like Lampard and convinced them they could achieve anything.
From the day he turned up at the England team’s hotel to personally introduce himself to the Chelsea players, through a trophy-laden three years, he formed a bond with his squad that lasted well beyond his first exit in 2007.
He was, for example, in regular contact with Lampard as the midfielder mourned the death of his mother in 2008. It is an example of the softer, human side of Mourinho that can be lost when focus is turned on to his more divisive characteristics.
And it is notable that for all of his tactical expertise, it is his man management that has stayed with Lampard, who is in the process of creating his own “family” at Chelsea.
It is debatable whether the methods that served Mourinho so well in the past are still applicable today. Public fallouts with Paul Pogba cast a shadow over his explosive reign at Manchester United - and his criticism of Tanguy Ndombele last season felt like he was heading down a similar route at Tottenham.
Ndombele’s turnaround, however, feels like a story from the start of Mourinho’s career and the manager who will face Lampard this weekend should be more familiar to the Blues boss than the sulking presence from Old Trafford.
While Mourinho has faced accusations of being outdated, Lampard has a very modern approach. He empathises with young men who make mistakes, rather than throwing them under the proverbial bus.
A quiet word was had with Tammy Abraham and Ben Chilwell for breaking ‘rule of six’ Covid guidelines recently. Likewise with Reece James when the right-back was sent off for dissent when playing for England: “none of us are saints” was the message.
It is an approach that is getting a response from his players.
“As a young manager, as players we learn a lot off him,” says Mason Mount. “He has been there done it in the game, so as players we can speak to him and learn about the experiences he’s been through. It helps us as players, so it is obviously good for us.
“I worked under him at Derby and now coming to Chelsea I haven’t seen too much of a change in him in the way he works and the way he is hasn’t changed that much since he’s come to Chelsea.”
That in itself is remarkable, considering the manner in which the pressure has been amplified since swapping Derby for Chelsea and the expectations of Abramovich.
He remains very much a novice up against the bonafide greats of Mourinho, Pep Guardiola and Jurgen Klopp. On Sunday, he will get a latest opportunity to prove the apprentice is up to the challenge of taking on the master and emulating Mourinho’s past triumphs in Abramovich’s next millennium.
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