Thomas Tuchel’s side had looked comfortable throughout, limiting Guardiola’s heavily attacking-orientated side to just two shots on target.
In fact, despite Guardiola facility to start a defensive midfielder and incorporate six players who prefer to attack in his side, it was Chelsea who had the better chances.
Timo Werner missed several gilt-edged chances, with Christian Pulisic also left feeling he should have done better with an opportunity after the break.
Despite those glaring misses though, Chelsea were able to break the deadlock just before half-time at the Estadio do Dragao.
Three minutes before the break, Mason Mount played a stunning defence-splitting pass through to record-signing Kai Havertz.
The German kept his cool to round onrushing City keeper Ederson and slot into an empty net, a goal that was ultimately enough to see his side lift the Champions League trophy.
While Tuchel earned many of the plaudits for once again getting the better of Guardiola tactically, Mourinho believes that Lampard deserves some of the credit.
Does Frank Lampard deserve any credit for Chelsea’s Champions League win? Comment below.
The Englishman spent 18 months in charge of the Blues, leading them to a top four finish and an appearance in the FA Cup final in his first season in charge.
That debut season began under the cloud of a transfer embargo, with Lampard forced to blood several academy players into his starting line-up.
One of the main beneficiaries of that was Mount, who was handed his debut by Lampard, and has gone on to become one of Tuchel’s most important players.
And Mourinho feels that Lampard should be hailed for the way he helped to develop the 22-year-old into such a key man.
“I watched him two seasons ago in his first [ Premier League ] match, Manchester United against Chelsea at Old Trafford, and I saw the talent but I didn’t see maturity or consistency,’ Mourinho told The Times.
“I put a little bit of a question mark over how long this boy would need to develop and become a complete player. He didn’t need long.
“I think he has to thank Frank because even with results not being wonderful he was always keeping faith in that kid. He gave him incredible conditions to develop.”
As well as praising Lampard, Mourinho also hailed Mount for his own playing ability.
“I believe he is an attack-minded player, a creative player, but he has the tactical discipline. Mount is a team player,” the Roma boss said.
“We see him now with [Thomas] Tuchel coming from the sides, when with Frank he was more of a No. 10.
“I think he is very, very intelligent on the pitch. From what I see, he has a very good understanding of the game. He has goals, which is an important thing for a midfield player. I like him very much.”