The former England international took over the reins of the west London club from Maurizio Sarri earlier this summer after the Italian returned to Serie A with Juventus.
Lampard led Derby County to the Championship play-off final in his first season in management before the Rams lost 2-1 to Aston Villa in the Wembley showpiece.
His performance as Derby manager was sufficient for Chelsea FC to give their record goal-scorer the chance to take charge of the five-time Premier League winners.
Lampard won two of his three Premier League titles as a player during Mourinho’s first spell in charge of the west London side between 2004 and 2008.
And the former Chelsea FC boss is hopeful that Lampard can prove a success but Mourinho was reluctant to go overboard about the 41-year-old Blues manager.
“You know, time will see,” Mourinho told Sky Sports. “Only time. It would be nice and easy for me to say, because I love him, that he’s going to be a phenomenal manager.
“It would be very nice for me to say, but I’m not going to say that, and I cannot also say I don’t believe he’s going to do it, because that’s not the way I feel.
“I feel that he has a potential, I feel that he loves, which is a very important thing, he loves – that’s the reason why he is there – and I wish him the best but only time can speak and in a few years we will see.”
Lampard will be tasked with steering the Blues to a top-four finish next term, as well as competing well in the Champions League.
Mourinho, on the other hand, is still waiting to return to football management after parting company with Manchester United in December.
The Portuguese head coach led Chelsea FC to the Premier League title in 2005, 2006 and 2015.
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