About 18 months ago, Mitch Marsh made a decision that changed his cricket, and his life in general.

The 25-year-old West Australian — proclaimed as Australia's answer to its perpetual all-rounder problem — was struggling with self-doubt over where his career was going and what he had to do to be successful.

Marsh found himself on the outer of Australian cricket, dropped from the side for the second Test against South Africa in Hobart, and with constant questions over his credentials at the top level.

"When you're working as hard as you possibly can to be successful, and it doesn't quite come off, it's very easy to get down on yourself," he said.

"I started to have a lot of doubts about what I was doing, and I sort of kept that very internal."

Marsh made the decision to open up about his doubts in an effort to turn his career around.

Marsh says he was struggling with self-doubt. ( ABC News: Robert Koenig-Luck )

"Once I was able to get those feelings out in the open, it gave me an opportunity to try and create a plan of what I wanted to achieve," he said.

"I sat down with some key people in my life and I did that.

"To have the summer I had last year, after being in those sorts of places, made it all worthwhile. And it was pretty awesome."

A transformed player

Marsh returned to the Australian side for the third Test against England in Perth last December, after undergoing shoulder surgery in the off-season which left him unable to bowl for several months.

But a scintillating start to the domestic season as captain for WA catapulted him into the national side, and he grabbed his opportunity with both hands to produce his best summer of cricket for Australia.

He finished the series with two centuries, including his maiden ton in front of his family at the WACA, and an average of 106.

Mitchell Marsh celebrates his first Test century against England at the WACA ground in Perth. ( AP: Trevor Collens )

Marsh is now touted as a future Australian captain and firmly believes in the importance of managing the mental side of sport.

"I think that's a huge side, not only of sport, but life in general," he said.

"For young guys coming into teams, being able to be open and honest about how they're feeling and not feeling like they can't speak up [is really important]."

Captaincy tested in difficult conditions

Marsh will captain Australia A's four-day side in the upcoming tour of India, and said he was looking forward to showcasing his leadership skills in difficult conditions.

With the ongoing absence of Steven Smith and David Warner from the national setup, the conversation around whether Marsh will take on a leadership role for Australia next summer will only increase.

"There's obviously going to be talk outside, but it's just about playing my role for the team," he said.

"I know that sounds so cliched, but I am going to go over to India, I am going to be the best captain I can be for the four-day side.

"And I'll try and be the best leader I can be in the Australia setup … and [if] that means I have 'C' or a 'VC' next to my name, that's irrelevant to me."

Australia A's tour begins with a series of one-day contests in August, before two four-day matches in September.