Steven Smith announced as Australian Test Captain, The GABBA, Brisbane. Photographer: Liam Kidston. Source: News Corp Australia

The 25-year-old will become Australia’s 45th Test captain and the third youngest in history when he takes the reins at the Gabba.

“It’s obviously been a pretty whirlwind 18 months for me personally and for the team as well,” Smith said.

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“For this to come up so quickly it’s an amazing thrill, it’s something that I’ve always dreamt of doing and to now have the opportunity to lead Australia in a Test match its an amazing thrill.

“I spoke with Michael this morning ... He’s very proud of me and he’s really excited for me this week to lead Australia.

“I'm extremely excited ... I’m looking forward to the challenge.”

With many touting Steve Smith as the man to eventually take over from Michael Clarke as Australian Cricket captain we take a look at the 25 year old's career wearing the baggy green

Smith said he would draw on his leadership experience with NSW and the Sydney Sixers and the advice of veteran teammate Brad Haddin.

“I know our senior guys will support me 100 per cent and Brad Haddin, who I’m really close with, will be right behind me,” he said.

“I’ll lead from the front with my performance on the field, with the tactics I think we’ve been pretty good this year ... I don't feel there is a need for a big change there.”

Smith has previously signalled his desire to move up the batting order into the No. 3 or 4 position and hinted that was a possibility in the second Test at the Gabba.

“I’ve been thinking about that for the last couple of hours,” Smith said with a smile.

“I haven’t made a decision with that just yet, I’ll see what the selectors do with the team and then I’ll make up my mind from there.”

Australia coach Darren Lehmann said Smith had already shown his leadership qualities at a state and international level.

“He’s always had the leadership qualities at state level first and foremost, and had success with the Sixers and NSW. More importantly it’s the way he has gone about it on and off the field within our group.

“He’s a young leader and we are looking forward to us going a long way with us for a long time.

“We are really proud of what he’s achieved so far and now the challenge is for him as the 45th Test captain is to get a victory for us in the second Test.”

Haddin will continue his duty as vice-captain for the rest of this series before stepping down when Clarke returns.

National selector Rod Marsh said Clarke’s injury dramas made for a difficult decision.

“These are difficult circumstances given Michael’s injury and the fact that we don’t know how long he will be out of the game,” Marsh said.

“What we do know is that it won’t be an overnight fix so after a lot of thought we have taken the opportunity to appoint an emerging young leader as captain until such time as Michael regains fitness and returns to the side.

“We congratulate Steve on the wonderful honour of leading his country. On Wednesday he will become Australia’s 45th Test captain and at the age of 25 will become one of our youngest leaders.

“He is an exceptional young man who is highly regarded by the National Selection Panel not only for his fine performances with the bat but also his maturity and clear leadership potential.

“Brad Haddin has done an exceptional job as vice-captain since assuming the role last year and will provide strong support to Steve just as he has done for Michael.

“There was a strong argument for Brad to assume the captaincy until Michael returns, but given we don’t know how long that will be, we felt the time was right to take a longer-term view and give a young player this chance.”

Smith will be 25 years and 197 days when the second Test commences at the Gabba making him Australia’s youngest captain in 35 years.

Aside from Smith, only Ian Craig (22 years and 194 days), Kim Hughes (25 years and 57 days) and Billy Murdoch (25 years and 324 days) have captained Australia before their 26th birthday in 1957, 1979 and 1880 respectively.

Australian batsman Steve Smith has scored a fine century against India, touchingly dedicating the hundred to fallen teammate Phillip Hughes.

Hughes, who was 140 days younger than Smith when he made his Test captaincy debut against Pakistan in Perth in 1979, told The Australian in November that Smith was the right choice to lead the Test team.

“What’s the point of picking Brad Haddin?” Hughes said at the time. “Give the young bloke a go. Smith did an outstanding job in last year’s ­Sheffield Shield final. He batted himself at three. He led from the front. He looks a natural to me and he’d have help there in Haddin behind the stumps. Australia will have a strong bowling attack for him to play with.”

Allan Border wrote in The Courier-Mail on the weekend that Smith was the man for the job.

“He is an impressive character and his batting is so good it now seems incredible he was first picked to play Test cricket as a leg-spinner,” Border wrote.

“He was always a big batting talent and I think he would be a good captain of Australia.

“One of the main things you want from the captain is to be safe in his selection in the team and Smith certainly ticks that box.

Former Australian skipper Kim Hughes has backed Steve Smith to lead the team in the Test arena.

“I get the feeling Smith will also be a regular in the one-day side. That is great because, ideally, you want your captain to have the job in Test and one-day cricket. It can get a bit unwieldy splitting things up.”

Smith captained NSW to the Sheffield Shield title last season and compiled innings of 75 and 103* in the final against Western Australia in Canberra. He has also captained the Sydney Sixers in the Big Bash League.

He produced the best year of his career in 2014, blazing 779 Test runs at 77.90 in seven Tests, including three centuries and four 50s.

Smith has scored 1,749 runs at 46.02 in the 23 Tests he has played since his debut against Pakistan at Lord’s in 2010. He has also played 45 one-day internationals and 23 Twenty20 Internationals.