Nickelback sunglasses concert Nothing like an Internet fight between two washed up rockers over a washed up pop princess!

Chad Kroeger is currently in Russia with his band Nickelback, where they put on a concert and held a press conference yesterday, but that doesn't mean he stays out of the drama back in the States!

The Canadian rocker and his fiance Avril Lavigne were mocked this past weekend by the "Complicated" singer's ex-husband Deryck Whibley, who decided to dress up as the engaged pair with his girlfriend Ari Cooper, and apparently Mr. Kroeger didn't find their costumes too amusing!

Avril's man fired back at the Sum 41 front man on Twitter, writing, "Hey Deryck loved the costumes! we were going to dress up as you guys this year but all the parties had celebrity themes haha! -CK."

Well, hey, at least this feud makes all the people involved slightly relevant again!