"England are hammering the Aussies in their own backyard." I think it's a metaphor of some sports game. It means "The England team is outscoring the Aussie team a lot in their own sports arena." For reference only. I wish it could help.

means your gf is aussie and you believe you represent all of england? :P

The English are talking about the Aussies behind their back?

I'm going to hypothesize. Backyard sports is a series of video games that play on computers or consoles and as said are very popular with children which is actually the target audience.There are almost all imaginable sorts of sports and comprise all the major US leagues(MLB,NBA,NFL,NHL,MLS). Following that hypothese the sentence means that some Englander is bragging that England is the best and bound to beat Australia all the time in their own backyard (in their own territory or the chosen type of game).;) Yeah, perhaps, Jura knows better.

The English are winning a sports game, but not just winning, they have taken Australian team to the cleaners, winning by a long shot and they have done it in Australia itself...Go on England!!