[Tishabet]

Believe it or not, I used to be a fairly serious dog sledding enthusiast, and I've been in my share of dog fights. I agree with the advice given above in terms of ways to prevent another incident. In terms of what to do when the dog is actually attacking you, here are some recommendations:
First, your "hammer throw" is similar to what dog drivers do. No animal (humans included) like the loss of power/control that comes with being lifted off their feet. I usually heft the dog over my shoulder and drop him on his back. Dogs REALLY don't like being on their back when they are in a fighting mood, it's their most vulnerable position. One of the first tests you do with puppies to determine their disposition is to flip them on their backs with their belly exposed and see how long you can keep them like that. An aggressive dog will HATE this vulnerability.
Second, if the dog has his jaws locked onto anything (you or your dog) there are a few good moves you can pull off to make him let go/retreat. First is the aforementioned lifting him off his feet. Other options: Go for the eyes. Enough said.
Another option: Dogs are sensitive under their chin. A good punch there will really stun a dog.
And last but not least, my preferred method: Choke them. It will take a few seconds, but if you can get your hands around a dogs throat and choke them, they'll let go because of laryngeospasm, the same reflex that often causes drowning victims to not aspirate water. Choking is my "go to" solution if one dog has his jaws locked onto another and won't let go.
FWIW, I've never kept a fighter and most of the other dog drivers I know have the same rule. If the dog starts fights, the dog has to go. No exceptions.