CARLTON captain Marc Murphy has come good on his promise to be an improved leader and is becoming an extension on the Blues' coaching staff, according to Brendon Bolton.

Murphy, whose leadership has been criticised in recent seasons, has become a pillar of stability during the Blues' surprising 3-4 start to the season, both on and off the field.

Bolton said the 28-year-old, who is in his fourth year as skipper, had grown in the role this season and justified his re-appointment just under six months since the club underwent a "reset" under its new coach.    

"One thing I've been really pleased with is how much the leaders and 'Murph' in particular have accepted me and some new ways of thinking," Bolton said. 

"But more importantly how much they've wanted to change and improve themselves.

"It's about emphasising messages from the coaches, it's about investing in other youngsters, and day to day all our leaders are doing that.

"If they can become an extension of the coaching group, that's really important to us."

When asked if Murphy was becoming an extension of the coaching staff, Bolton said: "Definitely, day to day … 'Murph' has been really consistent".

So impressive have the Blues been this season, Bolton was asked if there had been any talk of finals at the club during its three-game winning streak.

"That's an interesting question," he said.

"We're all about equilibrium, not getting too high or low … we have a long way to go," he said. 

Keeping a level head and understanding there is a lot to improve has been the focus for the Blues and Bolton described their recent form as "little steps in building confidence".

He said the players were gaining belief in the new coach's system, with their defence an area of great improvement (only the Sydney Swans in round two have scored 100 points against them this season).

Sunday's clash against Port Adelaide will see Carlton shoot for four wins in a row for the first time since round 21, 2011.

Veteran half-back Kade Simpson will play his 250th game, while key defender Michael Jamison will run out for his 150th.

"For a guy who's only slight in stature, what amazing courage," Bolton said of Simpson.  

"He goes back with the flight regularly and to his credit he's really solidified our defence.

"I'm proud for him and proud for his family.

"To play 250 in what I consider the hardest and most competitive sport to play in the world is a great effort and one that all Carlton members should come along and support this week."