"It's pretty crazy how it all works out," Marsh told SEN radio after being confirmed as Aaron Finch's replacement as T20I captain. "Very proud moment. Probably not something I'd ever thought I would do, but really looking forward to the opportunity of going to South Africa."

Marsh, who was an Australia Under-19 captain, previously relinquished the role at Perth Scorchers when he felt he couldn't give it his full focus as he tried to return to national colours, and last year largely ruled himself out of the ODI job after Finch's retirement - although national selector George Bailey believed that was Marsh not wanting the headlines - but nearly 12 months on, he is now much more secure of his standing.

"Guess I'm very proud that I've stuck at it, and been through a little bit of adversity through my career - through my own fault, mind you - but [it's] nice to be recognised in our group as a leader," he added. "Think anyone who works hard and is driven to succeed in whatever field they are in, and they come up short, it can be bloody hard to be honest with you, and I'm really proud of the fact I've never really given up.

"I've also [been] through those lessons learnt to enjoy every part of my life - the ups and downs - and try to take a lot of learnings from my failures, and understand that whatever you do in life - whether it's cricket, sport, [or] business - you are going to fail, and it's [about] how you deal with those failures. Hopefully that will help me with my leadership, and [in] trying to win a few games for Australia."

Marsh believes T20 cricket is the toughest format to captain, given the game can swing on very small margins, but he is looking forward to the challenge in South Africa. Although his appointment is only for that tour, he is now strongly placed to take the job full time and will a leading candidate to add the ODI format as well after this year's World Cup, with Bailey saying a single white-ball captain would be the preference.

"It's certainly the hardest [format]," Marsh said. "I've gave up captaining the Scorchers that was mainly around [when] I was really striving to play for Australia, and I didn't feel like I could give it everything. It's really hard to balance that. You've got to put a lot of time into getting things right tactically, but I'm really looking forward to the challenge and will have plenty of good people around me to help. I'll lean on others, which has been a really important learning for me as a leader."

Staying fit for extended periods has previously been one of Marsh's challenges. He opted to undergo ankle surgery last year which ruled him out of the BBL, and that is an issue which will need to be continually managed. But getting through three consecutive Ashes Tests was a big tick for him, albeit he did pull up sore at Old Trafford.

"I'll have to keep looking after myself and keep working with the great staff at Cricket Australia and the WACA, and make sure I can stay on the park as much as I can," he said.

Reflecting on how his Test career was revived in England, when he replaced the injured Green at Headingley, he added: "I probably spent a fair chunk of my red-ball career trying to bat like Steven Smith, Marnus [Labuschagne], Usman Khawaja - those guys that can bat for six hours - but ultimately that's not who I am; that's not me as a cricketer.

"I don't have the best defence, but I know when I'm in a really good frame of mind mentally and in an attacking frame of mind, that I can defend well and keep good balls out. Outside of that, I really want to play the way I want to play."