My GSD was attacked a few months ago. We were visiting another sports club, first time there. I was working OB with her on the field (I asked the head trainer if it were okay to bring my dog onto the field, he said it was fine, they worked OB on multiple dogs all the time).
My dog was getting ready to do a long jump, a mal (handler lost grip on her long line) attacked her from behind.
Long story short, my GSD wasn't injured. My GSD is dog reactive (I've worked on it a lot in the last 4 years and she is much much better), I was so worried it would set her back, fortunately it didn't. I was so horrified (I think I was more traumatized than my GSD
, not sure if that's a good or bad thing), I felt horrible for putting her in that situation
I would never knowingly put my dog in that position, if there is a slightest chance that she will get attacked by another dog, she doesn't need to be on the field.
I am not trying to make you feel worse
, but personally, I would only work your dog when there is no other dog around.