I had that happen to Becky once. Scared me to death, the judge too! She went flying through the air, landed on her back and tumbled a couple of times. Against AKC rules, the judge went over her and asked if we wanted to send her back through at a walk so she wouldn't be afraid of it. As of Sept. 1st. you can send your dog back over an obstacle such as this. Of course, you still NQ, but at least you get to leave the ring on hopefully, a positive note.