User blog comment:FairyRaven/Fairy Tail Chapter 314: Erza vs. Kagura, Review and Commentary/@comment-50.132.123.37-20130111105322/@comment-5268982-20130111110429

I think that she never drew her sword because she knew that when she did, she would not go easy on her opponent and would result in killing him. Besides, it's Mashima, I don't really think he would kill two characters at once (he rarely even kills characters anyway).