Despite the positive tone, Australia also recorded its biggest one-day rise in Covid-19 deaths on Monday.
Victoria State accounted for all 19 Covid-19 deaths in the past 24 hours making it a national daily record.
Officials said that there were 337 confirmed Covid-19 cases in Australia on Monday which makes it the lowest one-day rise since July 29.
"This is an agonizing day for the members of the 19 families who have lost a loved one to Covid-19 today," Michael Kidd, Australia's deputy chief medical officer, told reporters.
"We are now seeing the first promising signs of a significant decline in the number of cases."
The slowdown in cases comes more than a month after the nearly 5 million residents of Melbourne, the capital of Victoria, were told to stay home.
It also comes a week after most businesses in the country's second-largest city were ordered to close in an attempt to slow the spread of the virus.
With about 21,000 Covid-19 cases and 314 deaths, Australia has still recorded fewer infections and fatalities than many other developed nations. Outside the two largest states of Victoria and New South Wales, the virus has been effectively eliminated.
Desperate to contain the outbreak, Australia's states and territories have closed their borders and slowed a timetable to remove remaining social-distancing restrictions. Victoria will continue in a hard lockdown for at least another five weeks.
Prime Minister Scott Morrison said internal travel restrictions were likely to remain until at least Christmas.
Social distancing restrictions have devastated Australia's economy. Unemployment is expected to peak at 14 percent this year as the country enters its first recession in nearly three decades.