This unusual Mountain Plover was photographed by JAY PACKER near Abilene, Texas on September 10, 2019. The scapulars and wing coverts have worn and fresh feathers, indicating that it is an adult. The extent of the warm orangy wash on the chest/breast and, especially, the dusky tips to a couple of these orangy feathers on the left side of the beast are suggestive of its eastern Asian counterpart, Oriental Plover. While Oriental Plover is a highly unlikley vagrant to North America, it is a medium/long distance migrant, and there is a May record from Norway. If one were to occur in North America, we'd better hope that it is an adult with some obvious alternate-pattern feathering, else it would surely be overlooked.
The alternate-aspect feathers of the chest/breast area on Oriental Plover present a very different pattern to that of Mountain Plover, and any unequivocal elements of this pattern should confirm a bird as Oriental Plover assuming there are no contra-indications.
The structural differences are subtle, with Oriental Plover having a longer bill, longer legs (esp. exposed tibia), and slightly longer wings at rest.
On Oriental Plover the legs have a stronger yellow tone, and the tail base is darker and thus has less contrast with a narrower dark subterminal tail band.
Flight views would be the best way to ID one, since on Oriental Plover the upperwing and especially underwing are all-dark whereas other similar plovers, including Mountain Plover, have white lines along the edge of the greater coverts and the base of the primaries above, and extensive white on the underwing.
NOTE: I have cropped some images, and altered the exposure/color balance on some, to provide a range of impressions:
