And nowhere has that been felt more than in the back-row with debutants Phil Dowson and Ben Morgan, as well as the internationally inexperienced Chris Robshaw, filling the large boots left by former captains Lewis Moody and Nick Easter.
But one man remains from the trio who started the disappointing quarter-final loss to France in New Zealand, with Croft taking his England cap tally to 33 in victories in Scotland and Italy this campaign.
The three new faces have just seven appearances between them but Croft has quickly whipped them into shape, England's strong defence picking up the slack of an attack that has crossed the whitewash just twice so far.
That gives Croft the sense of experience beyond his years, but he acknowledges that his international peak has been reached in British and Irish Lions red [in 2009], not England white - something he's desperate to change.
"I keep getting called the old man of the back row but I would like to stress that I am only 26 so I think I am still relatively young," said Croft, who landed an early victory over Saturday's rival captain Ryan Jones in three competitions to launch SSErugby.com.
"The guys that have come into the back row have done really well and it is just a great thing to be a part of at the moment. It is full of enthusiasm and just full of guys who want to play well and work hard for each other.
"And in terms of being the old man, I am not sure about that and I would like to think I have a fair bit to offer still.
"I am not sitting here thinking I have done everything I can for England - far from it.
"I always want to improve and I will never come off a rugby pitch completely satisfied with the way I have played, whether it be a penalty here or a dropped ball there, there are always areas I can and want to improve.
"Things are going in the right direction and I think the new faces and the intensity that has rubbed off on everybody has certainly had the same effect on me.
"I want to win things and I know I still have areas to improve so I would like to consider myself part of that new and enthusiastic England too."
Wales' visit to Twickenham next weekend will pose the biggest threat to Lancaster's new-look England, with Warren Gatland's side having scored six tries compared to Charlie Hodgson's two.
And with a backline that boasts George North, Jamie Roberts, Leigh Halfpenny and Jonathan Davies, much has been made of the attacking threat posed by England's visitors.
It makes the battle up front all the more important where England will run into Lions prop Adam Jones, but with Alex Corbisiero in the Red Rose ranks, Croft believes his side have nothing to fear.
The London Irish man has been taken the lead in England's front-row with Andrew Sheridan now retired and has produced some sterling performances against Scotland and Italy, keeping Martin Castrogiovanni quiet and Croft believes Corbisiero has been a revelation.
"If people are questioning how Alex will fare against the likes of Adam Jones against Wales then I think they have nothing to worry about," added Croft.
"Alex obviously had a very tough test against Italy in the form of Martin Castrogiovanni and fronted up to that superbly and showed what he is about.
"I think Alex is fully aware of the challenge that awaits him against Wales but he has done it all before, for both club and country.
"And he has got on exceptionally well in an England shirt and he has gone from strength to strength in every game I have seen him play and doesn't look like slowing down.
"He might be a young guy but he has coped with the pressure very well and when the spotlight is on you and the team that isn't easy.
"But Alex isn't overawed by it all at, has come through every test with flying colours and I wouldn't back against him to continue that against Wales."
Tom Croft is an ambassador for SSE. To check out Tom going head to head against Wales' second row star Ryan Jones in a series of three video challenges, head to www.sserugby.com and see who wins!'