Wires and banana have it right. Serabee was ridiculous and terrible. All she did was run up and down all over the place except for the melody. And this after Blake told her to reign it in. She did the opposite. Good idea to ignore your coach, Serabee!
Dia, on the other hand, was perhaps a bit uncomfortable with that song but she sang it fine imo, and has a terrific voice at all other times. Not only was her audition fantastic, but you can see her kick tremendous amounts of ass on YouTube:
Roses
Jar of Hearts
The Cave