Chris Brown has fired back at country star Miranda Lambert and critics who took aim at Grammy Awards producers for inviting him to perform at music's big night on Sunday.
 
The R&B star performed twice and picked up the Best R&B Album prize - but many industry executives, fans and stars felt he shouldn't have been there on the third anniversary of his infamous fight with ex-girlfriend Rihanna, which landed him in court on assault charges and resulted in a hard labour sentence, five years' probation and an order to stay away from the Umbrella star.
 
Outspoken Lambert was one of many stars who took to Twitter.com to express her disgust at seeing Brown onstage at the Grammys.
 
The singer, whose parents ran a shelter for abused women when she was growing up, wrote, "Chris Brown twice? I don't get it. He beat on a girl... Not cool that we act like that didn't happen."
 
But defiant Brown isn't about to let all the criticism ruin his big win.
 
In a tweet on Tuesday, he raged, "Hate all u (you) want becuz (because) I got a Grammy now! That's the ultimate f**k off! I'm back so watch my back as I walk away from all this negativity."