A deflected free-kick from Yu Hai was the difference between the two sides in Brisbane but Saudi Arabia wasted a host of chances to secure victory for themselves.
Naif Hazazi was guilty of the worst miss after he failed to convert a 60th minute penalty, the midfielder appearing too casual in his run-up, and seeing Wang Dalei save his weak spot-kick.
However, Olaroiu refused to blame the 26-year-old and insisted his team were unlucky not to claim something from their opening match in Group B.
He said: "We were unlucky today, more than unlucky.
"[In the] first half we didn't find the space to play and use our speed up front. Second half we created a few situations, and we had a penalty.
"We still have a chance to qualify as it is not finished, I hope the players play with the same determination and spirit [in the next game].
"The players should not lose their confidence."
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