Marsh is stepping in for injured one-day captain Pat Cummins while Cricket Australia has yet to decide on a T20 skipper for the long term following the retirement of Aaron Finch.
Being named captain of the limited overs sides continues a memorable year for Marsh, who got married in April and scored a century on his recall to the Test squad during the Ashes.
“It’s certainly been a crazy year. Throw in getting married, it’s been a good one,” he told reporters in Sydney. “We’ll get through South Africa and see how we go. I’m available to captain for as long as the team needs me. We’ll see where it all ends. I’ve come a long way as a person and learnt a lot captaining Western Australia, having great people like (coach) Adam Voges and Ashton Turner around me to learn as much as I can.”
Cummins, who also captains the Test side, is expected to link up with the squad in India ahead of the 50-overs World Cup which starts in October.
Marsh said he would probably not “try to reinvent the wheel” while captaining Australia for three one-dayers and five T20s in South Africa.
“It (captaincy) sounds pretty good, doesn’t it? It’s a very proud moment,” Marsh said. “I probably won’t try and reinvent the wheel. I think the most important thing I’ve learnt about leadership is staying true to yourself.
“Hopefully I’m a good captain. If not, I won’t be in the job for very long. That’s OK. I’m just looking forward to the opportunity.
“Have certainly felt a lot of love over the last few months. I just loved how invested our fans were in the Ashes, losing sleep. Not sure there was much work being done around Australia at that time.”
Marsh is looking forward to seeing left-arm pace bowler Spencer Johnson push for a potential debut in place of injured regular quick Mitchell Starc.
Young legspinner Tanveer Sangha will also hope for a debut.
“We haven’t seen much of him, have we?” said Marsh of Johnson. “I remember commentating a game and he was bowling 150 (kilometres per hour) and swinging them both ways. He’s an incredible talent.
“I faced him in the one-day final at the WACA and was blown away by his skill and his pace. Think he’s going to feel right at home in international cricket.
“(Tanveer has) got me out a couple of times. With that cheeky smile ... it’s always hard to take. He’s a very smart young bowler. From what I can gather and what I’ve heard, he’s a very good cricketer. A super talent.
“Think there’s no doubt we are going to see them in Australian colours over the next few years and we’ll get a look at them in South Africa,” he said.
Steve Smith is among the tour’s absentees while recovering from a wrist injury which he carried during the Ashes.
Smith yesterday revealed he had torn a tendon in his left wrist during the second Test at Lord’s, which had ended his hopes of trying his hand at opening in the T20 series in South Africa.
“It’s kind of the dream job. Everyone wants to open the batting in T20s,” he told Australian broadcaster Fox Sports. “There’s not much accountability there, you just sort of go out there and play.”
