Saudi Arabia, with a vocal away contingent at their backs, appeared to have scored a 93rd-minute winner from a free kick but the goal was dramatically ruled offside.
While the Saudis dominated possession, Australia had the better of the chances in front of 27,491 fans at Melbourne's AAMI Park.
Coach Tony Popovic will also sweat on injuries to Ajdin Hrustic, who was withdrawn at half-time, and his replacement Nishan Velupillay, who made way for debutant Anthony Caceres in the 74th minute.
Nishan Velupillay (2nd L) also copped an injury and was replaced. (Joel Carrett/AAP PHOTOS)
The result puts pressure on Australia to snare a result against Bahrain in Riffa on Tuesday night (Wednesday morning AEDT).
The top two teams in group C secure direct qualification for the 2026 World Cup while third and fourth place go into the next round of qualifying.
The Socceroos currently sit second in group C, on six points behind leaders Japan (10 points), and ahead of the Saudis on goal difference, while Bahrain (five points) play China (three) later on Thursday.
Japan play Indonesia (three points) on Friday.
Despite some sloppy passing and at-times shaky build-up play that almost let the Saudis in multiple times, Australia still had several quality chances go begging.
From a drop ball in the 12th minute, Cam Burgess hoofed the ball over the Saudi defence.
Mitch Duke beat Saudi goalkeeper Ahmed Al-Kassar to the ball before the pair clashed heads.
The referee initially awarded Australia a penalty but replays showed the contact occurred outside the box.
Popovic and counterpart Herve Renard had a heated exchange as both players received treatment.
Mitch Duke went down after a clash of heads. (Joel Carrett/AAP PHOTOS)
Hrustic lifted the subsequent free kick into the area where Lewis Miller's header deflected into the path of Harry Souttar, who blasted over the bar.
Australia improved after the half-hour mark and Hrustic spurned a golden chance in the 45th minute.
Aiden O'Neill forced a turnover with an excellent challenge on Nasser Al-Dawsari, with Duke squaring the ball to Hrustic, who fired a tame shot straight at Al-Kassar.
Jackson Irvine curled a shot over the bar late in added time, while Hrustic went down in pain.
Velupillay was hurt after he collided with Saudi defenders as he burst into the box.
In the 84th minute, Lewis Miller slipped through substitute Brandon Borrello, who burst forward and attempted to square it to Riley McGree, who was thwarted.
Riley McGree rues an opportunity missed. (Joel Carrett/AAP PHOTOS)
The Saudis almost took the lead when a late free kick deflected out to Sultan Al-Ghannam, whose long-range strike nestled in the back of the net.
But as the Saudis wheeled away, the linesman disallowed the goal, as Ali Al-Bulayhi had played at the ball, therefore interfering with goalkeeper Joe Gauci from an offside position.
McGree had an audacious bicycle kick flick wide of the near post in the 97th minute.
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