Australia defeated Denmark by a-lone goal at the Al Janoub stadium to progress from Group D with six points.
Australia secured their second victory at the mundial after beating Tunisia in their second group game.
Mathew Leckie's second half winner ensured that Graham Arnold's Australia secured their second qualification from the group stage of the World Cup in five attempts.
Australia was able to secure their first clean sheet in 12 games against European opponents to send Denmark packing from Qatar.
Mathew Ryan denied Mathias Jensen the opener on the 12th minute for Denmark, as he saved his shot to the right side of the post.
Meanwhile Tunisia were able to beat reigning World champions France by 1:0 in the other group game, but it wasn't enough to propel them into the round of 16.
Mitchell Duke's forced Kasper Schmeichel to a save from the edge of the box with 3 minutes to end a quiet first half.
Mathew Leckie received a fine pass inside the 18-yard box, before he sent a stunning strike inside the bottom right corner to send Kasper Schmeichel helpless on the hour mark.
Joachim Andersen connected Chritian Erickson's corner but it went off wide.
Alexander Baah missed a glorious opportunity to restore parity for Denmark, with 2 minutes to end proceedings, after striking the right post.
Mathew Ryan made a great save again to deny Denmark after saving Kasper Dolberg's low shot from inside the box in the additional minutes of the second half.
By: Abdul Razak Salim