Bird Identification: Need a positive ID on this bird. , 1 by kawasemi

kawasemi wrote:
Hi Resin, Excuse me for this late reply, and thank you so much for the interesting diagnosis. I did take a few more photos, and judging from what you said, the brownish gray underparts point more towards Pallas's. What's your take on the wing coverts? Perhaps the photos are not sharp enough to get a clear idea of the bill size, I'm afraid, but hopefully you can feel more confident in identifying the bird now.

Kawasemi