The Syrians, competing at the 16-team finals for the first time in 15 years, fully deserved the victory with players and substitutes sprinting over to their delighted supporters at the Al Rayyan Stadium to celebrate and pray.
The win was their first over the Saudis since 1976 and only their second in 24 attempts.
"This is a battle and we have not yet won the war. The difficult part is just starting," said Tita Valeriu, who last month was appointed the team's fourth coach in a year.
The shot was then diverted past Saudi goalkeeper Waleed Abdullah by his full-back Abdullah Shuhail's slight headed touch.
The Saudis improved after the break and drew level in the 59th minute when substitute Taiseer Al Jassam leapt into the penalty area to head Mosab Balhous's punched clearance from a corner back past the Syrian goalkeeper.
They were back cheering again just four minutes later, however, when Al Husein's right footed shot from just inside the area took a wicked deflection past Abdullah to restore the advantage.
"I like very much the fans and spectators, they were like the 12th player in the game," Valeriu told reporters.
The defeat left Saudi Arabia's Portuguese coach Jose Peseiro under more pressure after he was criticised for their failure to qualify for the World Cup for the first time since 1990 last year, despite joining midway through the qualifying campaign.
"We lost the first game but I believe we can win other games. Spain lost the first game in the (2010) World Cup and won the World Cup," said Peseiro.
