By the time I had all that taken care of, it was clearly too late to pre-ride. Or warm up, really. I was already starting to have visions of the beginning of my season.
The race itself ended up going okay for most of it. Crossing the finish line to start the last lap, I was sure I'd just been lapped by the lead riders, so I sat up. I noticed that everyone else around me was still going pretty hard, so I started working again. Of course I lost a couple of places.
Anyway, the course was mostly flat and relatively non-technical, although some gravel and loamy corners were a little hard to ride cleanly. However, it ran through a sand pit. On the first several laps, I was able to maintain traction and ride it. However, on the last lap, that was not to be.
I lost traction and went down in the sand. I was up fast, but someone was right on my wheel, and when I fell down, he fell on my wheel. Literally. Then either he or the guy immediately behind him fell down too, and landed heavily on my wheel. I had that sinking "broken component" feeling after the first impact. But then I had a much better idea that my race was over. Still, I grabbed my bike, ran the rest of the pit, and tried to ride away. It didn't work. I tried unhooking the rear brake, but still no love. So I threw the bike on my shoulder and started running. Then I thought, "I'm at the back of the race somewhere already, and I'm a lot slower on foot... by the time I reach the finish line, it'll be over." So I walked off the course. At least I completed enough laps to count as finishing in that strange way that this stuff is handled in 'cross.
Looking at the pic, I think the sequence of events is a little different from what I thought - I think maybe I was off and running before wiping out, then went down as a result of the guy behind me plowing into me, which is probably also when my rear wheel was destroyed. The guy behind him is the one I remember falling on it, so the first guy must have rolled out of the way between after tacoing my wheel, so that the second guy could come in and look guilty.
Anyway, this is Adella's picture of my rear wheel when I was telling my friend about it after the race.