User blog comment:Zathronas/Analysis by an author: Beacon Glynda Goodwitch/@comment-6830001-20131213005244

It's just some conjecture without much facts to complete it but here I go :

We saw that Roman was already known for his previous "criminal" actions as seen in the plane to Beacon. I might just think that as people were afraid of him in the beginning of episode 1, Glynda could have heard that he was there so she did her job as an Huntress by fighting him and Cinder. She protected Ruby because she didn't want an innocent girl to get involved in this. Then, Ozpin having heard of a scythe user girl, decides to meet her and we know what happened after...