Saudi Arabia gave China its first defeat under new boss Gao Hongbo with four goals at an international friendly here on Thursday.
"In the first half there was balance between the two teams, but in the second half and the last part of the game we are better," said Saudi head coach Jose Peseiro.
"The players were not concentrated enough in the first half, and they played slower than they did in the last two games," commented Gao.
"To face a technical side like Saudi, we need to pressure them tightly with concerted moves. But as we have short time in training, I think the players have done well in this respect. The defeat will not affect our confidence."
China had showed some good form recently, fighting out a surprising 1-1 draw with European powerhouse Germany and beat Iran 1-0. But the Saudis, who are preparing for their World Cup qualifier against South Korea, were the better side of the night.
Ace striker Al Qahtani opened the scoring with a curved header in the 6th minute, before Jiang Ning levelled for the hosts on 34 minutes after he stole a ball from Alqadi Naif Ali and firing a diagonal shot into the far post.
The guests doubled the advantage before the break with midfielder Hawsawi Mohammed Noor netted home a header inside the box following captain Sulaimani Hussain Omar's freekick. Substitute striker Hazazi Naif Ahemd made another in a counter-attack, before Binsaran Nasser finished off the night with a penalty.
China had several good chances in the match. Zhao Xuri had two consecutive shots in the first half, but his out spinning shot was denied by the near post and the second drive was parried by a focused keeper Ali Waleed Abdullah.
Saudi Arabia will play South Korea on June 10.