It comes from a real confidence boost in the transfer market after the signings of Timo Werner and Hakim Ziyech.
The duo officially became Chelsea players today, though when they join up with the squad remains to be seen.
But their captures have created a real buzz around Stamford Bridge, both with fans and players.
Lampard is in his first season in charge at Chelsea and has performed admirably considering his lack of experience.
The Blues look on course to land a spot in the top four of the Premier League and have made it to the semi-final of the FA Cup.
But Sky Sports pundit Merson reckons Chelsea are not far off and that the win over Pep Guardiola's men last week was a huge boost for Lampard.
"To go and beat Man City was massive," he said, speaking to Sky Sports.
"It was massive because everyone is looking to close the gap.
"Chelsea have got nice fixtures between now and the end of the season, so I don't think there's any way they're not finishing in the top four."
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Lampard is expected to continue spending in the transfer window, with Leicester star Ben Chilwell and West Ham's Declan Rice on the radar.
Merson added: "I think Chelsea need a left-back, and they might need another centre-half, and then they'll be a major force next season.
"I don't think they'll win the Premier League next season, but the gap won't be as big.
"They mean business. The owner has been brilliant; he's weighed it up and gone: 'Bang! Here's your money'.
"He's looked at the situation and thought, 'Tottenham are struggling, Pep Guardiola won't be at City forever', and he's trying to get into the top four, close the gap and challenge when they have their chance.
"In three or four years, I'd be quite shocked if Chelsea don't win the Premier League."