Combat Ponies

Nothing really hard hit, but this is a question that has always plagued me. How exactly would an Earth pony rate up to a Pegasus or Unicorn pony in combat. Unicorns have magic which, if you think about it logically would make them an all around better fighter, just being able to levitate a weapon alone would be a tremendous upper hand compared to a Pegasus or Earth pony. Speaking of which Pegasus pony are able to fly, which again is a large upper hand compared to the Earth pony. I honestly can come up with a few different theories that would work in an Earth ponies favor, but I'd just like to see if anyone else has had this problem.