Although Jiang Yi was not a Quasi-Saint, his strength was sufficient to rival one. As the reincarnation of the Great Ancient Witch Da Yi, his foundation from a previous life enabled him to battle beyond his level.
The fact that Jiang Yi was the reincarnation of Da Yi was no secret among the Human Race, and indeed, within the entire Three Realms. After all, there was only one archer as proficient as Hou Yi in the Prehistoric World, and he was related to the Witch Clan, with an identical name at that.
It was almost like having written "He is Da Yi" in large characters across Jiang Yi's face. As long as they were not blind, any powerhouse from the Prehistoric World could recognize that Hou Yi was the reincarnation of Da Yi.
However, even though all the masters from the Prehistoric World knew that Hou Yi was the reincarnation of Da Yi, he himself was oblivious to it, instinctively overlooking this fact.