Australia's benchmark S&P/ASX 200 Index dipped into negative territory Wednesday, Sept. 27, suggesting the world's second-worst performing major stock market is in for more trouble, according to data from Bloomberg.

The selloff comes as investors lick their wounds following local earnings season. Performance has also been hindered by global tensions with North Korea that have led to banking concerns down under.

If the index, which tracks equities on the Australian Securities Exchange, goes below 5,629 points, the current correction could extend another 3.6%, Morgans Financial Ltd. analyst Violeta Todorova recently wrote in a note.

At the market close on Thursday, Sept. 28, the index traded slightly up 0.11% to 5,670.40. So far this year, the index has gained only 0.1%, compared to the U.S.'s S&P 500 Index's 12% gains.

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