Wildlife Spotting

Duck seen at local duck pond brown colored head and brown and white markings.
I have received several suggestions that this is a Anas platythynchos mallard there are several Anas platythynchos ducks in this park i am quite familiar with them but this perticular duck has no green or gray on him and looks nothing like the Anas platythynchos ducks except for in body shape he is also much larger in size so unless this is a color mutation of Anas platythynchos i dont know about it is deffinatly not a Anas platythynchos mallard. Any help iding this animal would be great alot of people are curious as to its name