The Blues are currently third with eight wins from 12 Premier League games, despite not being able to sign any players until 2020 due to a FIFA transfer ban.
In just his first season in charge of the club where he made his name as a player, Lampard has thrown his faith into the club's young stars - so often neglected during the Roman Abramovich era.
One of the victims of that era was Mancienne, a prodigious talent who eventually left the club in 2011 after making only six first-team appearances.
Others might feel bitter over seeing youngsters finally given a chance at Stamford Bridge, but Mancienne told Tribalfootball: "I'm buzzing for Frank to be honest and I'm really happy for the young players.
"I hope Frank does well, especially using the young players as well."
Tammy Abraham, Mason Mount, Reece James, Callum Hudson-Odoi and Fiyako Tomori have all found regular playing time this season, with teenagers Billy Gilmour and Marc Guehi also featuring.
And Mancienne revealed he was impressed with Lampard's youngsters while training with the club before his switch to New England Revolution in August 2018.
"They've got some great young players in their squad," he continued.
"I trained with them before I was coming to the MLS, I trained with them a little bit just to get a bit of fitness and some of the young boys are amazing and they deserve their chance.
"It's good they're getting that chance and to be honest if England as a whole wants to be a better (football) nation going forwards they need to give trust to the young boys and give them that opportunity and that experience otherwise how are you going to improve?
"That's what countries like Germany do, they'd rather put a young boy through rather than buy someone. And that's why their national team has done better over the years."
Mancienne was also part of a talented crop of youngsters at Chelsea, and collected a FA Cup winners medal and the club's Young Player of the Year in 2008/09.
Despite his promise, Mancienne struggled to break into a team brimming with world-class talent in defence.
"Yeah most definitely. Because you're surrounded by world class p[layers so it makes you a better player anyway, so having the trust of a top manager as well gives you even more confidence and you're always improving.
"I felt like after, especially when I was a young boy at 16 training with the first-team, that when I went back down to my age group I felt like I was three steps ahead of everyone else because I'd been marking somebody who I couldn't get close too - it just made me a better player."
There has been plenty of criticism of Chelsea's 'loan army', which was dramatically reduced this summer due to the transfer ban.
Kenneth Omeruo, who has since joined Leganes, told Tribalfootball last year that the system was beneficial for his career, and Mancienne has repeated those sentiments when asked about his time with QPR and Wolverhampton Wanderers.
"I think it definitely helped my career as well. You get out on loan and you're getting first-team football and that's the most important thing.
"You want to be in the spotlight and making a name for yourself, you can't just sit there and just hope... especially at the time it was difficult to get a game or to be looked into because Chelsea is a massive club, they're going after trophies, managers obviously fighting for their job and not really trusting a young player at the time.
"Obviously now they've had to play young players which is massive and it's a massive opportunity for those young players and I think a lot of them are taking that opportunity. The loan system does work, you get minutes under your belt and you know what it's like to play real mens football."
Mancienne eventually left Stamford Bridge for Hamburg in 2011 before returning to England with Nottingham Forest in 2014, and is now in Boston with the Revolution.
Asked if he still has a soft spot for the Blues, Mancienne admitted: "Yeah I'm a still Chelsea supporter. They are my boyhood team so I still keep up with the results."