I'm betting you hit a little f&*$-you shoulder on that first rock. You can't see it from the eddy, but if you cut the rock too close on your left-to-right move just above Tombstone, you will catch it and get messed up. I broached on Tombstone because of that on my first UY trip, and almost slid left backwards and upside down. I got lucky. Glad you did too!