The war-torn nation salvaged parity after Hertha Berlin's Mathew Leckie was adjudged to have nudged Soma in the box. The big striker made no mistake from the spot. Soma also scored the late leveler against Iran that got Syria to this point.
Australia, who are looking to qualify for their fourth straight World Cup, took the lead early courtesy of Bochum forward Robbie Kruse. But Syria clawed their way back in to the game and deserved their equalizer, though the award of the penalty by Iranian referee Alireza Faghani was somewhat contentious.
After Thursday's match, which was played in a neutral stadium because of the conflict in the Middle Eastern nation, the sides will travel to Sydney to settle the outcome on Tuesday night. The winners will go in to another playoff with a CONCACAF team – possibly the United States – for a spot at the 2018 World Cup in Russia.
Both teams looked nervous early on with Leckie wasting a good chance for the visitors and Omar Khribin also guilty of profligacy for the "hosts."
But Leckie made amends in the 29th minute when he cut inside and unleashed a shot which deflected in off Kruse.
Syria should have leveled on 78 minutes but Socceroos keeper Mathew Ryan managed to block Soma's close range header. Even after Soma tucked away the penalty, Syria had another chance but Ryan brilliantly tipped Omar Khribin's effort over the bar.
"I think we were a bit unlucky. I'm not sure what happened with the penalty - maybe it touched his hand? I don't know," Australia's stand-in captain Mark Milligan said. "We're very confident. We'll go home and get them on a good pitch in front of our home fans."
Soma expects a tough match next Wednesday but has retained his belief: "In the first half we weren't as good as we should, but in the second we took control of the match until the last minute," he said.
"The match in Australia will be difficult, in front of their supporters and at their home venue... but there's no impossible in football."
mp/dv (Reuters, AP)