Lampard has called on his old club to be patient with the Italian.
He told the Daily Star: “It might take him a bit of time. It was a disappointing season last year.
“Chelsea are a club which wants to be in the Champions League every year. It's not that simple any more because the competition is much tougher.
“So for Chelsea the first aim is to get back into that top four. But it might take a bit of time for a new manager to bring in his new ideas."