Rohit's belief stemmed from the Australian cricketers' familiarity with Indian conditions and players due to the IPL and Champions League and cautioned the hosts to guard against complacency while taking on the visitors in the lone Twenty20 and seven-match ODI rubber.
"They are a very competitive side with most of their players having featured in the IPL and Champions League. They know the Indian conditions well. We can't get complacent against them. Australia on a given day are a very dangerous side," Rohit said in an interview.
The series starts with a one-off Twenty20 International on Thursday in Rajkot.
Rohit differed from the view that Australia have arrived in India with the least experienced squad and rated their batsmen as "match winners".
"They are still a very competitive side. Their batters are match winners. We have to be at our best against them."
Australia would be playing without their regular skipper Michael Clarke, who has opted out of the series due to a low back injury, and Rohit said the visitors would definitely "miss his experience".
Rohit also rubbished former Australian captain Ian Chappell's views that the upcoming ODI series has been "badly-timed" and will dent the team's morale by exposing its "glaring" batting frailties on spin-friendly tracks.
"I don't agree with his views. For me, every series is important whenever it is played. India-Australia series is always important for cricketers from both sides. The last thing a player, a sporstperson wants is to sit back at home and not playing the game," he said.
With each fielding team given two new balls to be used in alternate overs, one at each end, Sharma said it would make the job of openers a lot more responsible.
"You need to be cautious with the new ball upfront. You have to plan your strategy accordingly. The shot selection becomes important for you as an opener, like what shots you have to play, which areas you have to go after. The new rules are more helpful to bowlers," he said.
Rohit, however, refused to bring in any change to his style of play.
"Everything will remain same to me and I am not going to change my style of play. I am not going to make any changes in my batting technique," he said.
On Yuvraj Singh's comeback to the Indian team for the Australia series, Rohit rated him as "one of the best middle-over batsmen" India has ever seen.
"He is an experienced guy and his experience will definitely help the team against the Australians. He is a great batsman. He is one of the best batsmen India has ever seen in the middle overs," he said.
Yuvraj scored 389 runs in 334 balls on his comeback trail, averaging 64.83 in six matches against the West Indies 'A' and in the Challenger series.
Asked what would be the game without batting great Sachin Tendulkar once he announces retirement from international cricket, Rohit said it will be a "big loss" to Indian cricket.
"It will be a big loss to Indian cricket. He played his last game for Mumbai Indians in the Champions League final, so it's a big loss to our franchise also. We, at Mumbai Indians, will definitely miss his inputs.
"But everyone has to go at some point of time in his career. You can't do anything about it. We will try to have him related to MI in some capacity," he said.
Rohit said the Mumbai Indians captaincy helped him evolve as a "better player" which saw the franchise completing a grand double in 2013 - IPL and Champions League triumphs.
"Definitely, it has done so. It brought a sense of responsibility in me. It was a huge challenge for me to captain the side but I am lucky to have such great set of players and support staff. After Ricky Ponting stepped aside, I took over the charge from him and I am happy that I responded well to the situation. I would like to thank all in my franchise," he said.
Talking about the 2014 IPL players' auction, Rohit said, "every franchise would be happy to have the same set of players."