Investors have had just their second November session of losses on the Australian market after momentum created by hope for a coronavirus vaccine eased.
The S&P/ASX200 benchmark index closed lower by 31.5 points, or 0.49 per cent, to 6418.2 on Thursday.
The All Ordinaries closed down 31.7 points, or 0.48 per cent, to 6619.4.
The indices were little changed after the first two hours of trade, following mixed results on Wall Street.
However two bursts of selling without any obvious news ensured the market finished lower.
Investors sold stocks in sectors hardest hit by the pandemic, such as energy. They had this week gobbled up those stocks after Pfizer said its vaccine in development was 90 per cent effective.
Energy, financials and materials lost about one per cent or more.
Investors reverted to buying the technology and telecommunications stocks they have favoured during the pandemic.
Telecommunications was higher by 1.88 per cent, followed by information technology, up 1.07 per cent.
CMC Markets chief strategist Michael McCarthy said the ASX result showed investors' boost from Tuesday's vaccine news had worn off.
However this did not necessarily mean a move by investors into stocks that had gone unloved during the pandemic, such as energy and banks, was over.
"The sellback has nowhere near erased the gains," he said.
"We are seeing a turning of the mood and we're seeing it across asset classes."
The energy sector gained more than 13 per cent across the Tuesday and Wednesday sessions, so remained well ahead.
"Markets rarely go anywhere in a straight line," Mr McCarthy said of Thursday's losses.
Tasmania is forecast to plunge into a record $4.4 billion of net debt as it embarks on infrastructure spending to rebuild its coronavirus-hit economy.
The budget is headlined by $5 billion for infrastructure over four years, with about half of that set aside for roads and bridges.
On the ASX, Wesfarmers reported Bunnings reaped 25.2 per cent more in sales for the four months to October than it did for the same period last year.
Officeworks sales improved 23.4 per cent, online outlet Catch gained 114 per cent, Kmart was up three per cent while Target fell 2.2 per cent.
Wesfarmers shares finished up 2.54 per cent to $48.78.
Insurer Medibank Private said it was raising its policyholder growth target for the financial year to two per cent after good progress.
The news from its annual general meeting was followed by shares closing 1.79 per cent higher to $2.85.
Nine Entertainment says the advertising market has improved and it expects 15 per cent revenue growth from metropolitan areas in its second quarter.
Major events such as the NRL finals have helped it improve from a 15 per cent loss in the same type of revenue for its first quarter.
Shares were higher by 5.08 per cent to $2.48.
Telstra will undergo its biggest restructure in 24 years, splitting its business into three entities.
The new divisions under the group umbrella are InfraCo Fixed, holding its infrastructure assets, InfraCo Towers, covering its mobile towers and ServeCo which will look after customers and product development.
Shares were up 3.01 per cent to $3.08.
Earlier in US markets, there were mixed results after investors returned to buy stocks in tech giants and moved away from economically sensitive sectors as they weighed COVID-19 vaccine progress against a virus surge.
The Australian dollar was buying 72.62 US cents at 1727 AEDT, lower from 73.09 US cents at Wednesday's close.
ON THE ASX
* The S&P/ASX200 benchmark index closed lower by 31.5 points, or 0.49 per cent, to 6418.2 on Thursday.
* The All Ordinaries closed down 31.7 points, or 0.48 per cent, to 6619.4.
* At 1727 AEDT, the SPI200 futures index was lower by 15 points, or 0.23 per cent, to 6415.
One Australian dollar buys:
* 72.62 US cents, from 73.01 US cents on Wednesday
* 76.39 Japanese yen, from 76.89 yen
* 61.73 Euro cents, from 61.78 cents
* 55.05 British pence, from 55.09 pence
* 105.77 NZ cents, from 106.00 cents.