Nicky Hayden injured his left hand when he fell from his factory Ducati in the final 15 minutes of qualifying at Brno in the Czech Republic.
The American now faces the painful prospect of 22 laps with a chipped radius (wrist) bone in Sunday's race, which he will start from eighth on the grid.
“We started out well and on my first exit on a hard tyre I was able to improve my lap time quite a lot," began Hayden. "We got into the 1'57s quite quickly and I thought we were in good shape to have a shot at a good grid position.
"Unfortunately my first flying lap on the softer tyre ended in turn three – I just lost the front quite early on entry, I don't know why. I know people always says 'I did nothing different!' but honestly, even looking at the data, the brake pressure and speed was the same as my previous runs. We need to have a look at that and understand it tonight.
"Luckily it wasn't too heavy and everything on my body is fine other than my left hand. It must have got caught under the bike because it's very sore and even though we tried to go back out I couldn't change direction.
"We've had it checked out by x-ray which showed we took a chunk off the tip of the radius, which isn't good, but my scaphoid is okay and that's the main thing because I have a screw in there and it's not damaged. Just walking around the paddock it's not too painful but we'll have to wait and see how it goes over 22 laps on the bike tomorrow.”
Team-mate Casey Stoner will start from the front of row two, in fourth, after a busy session spent trying to get his Desmosedici balanced.
“We hoped we could make progress in qualifying this afternoon but at the beginning every setting we tried seemed to go in the wrong direction. When we got the front working better we encountered a problem with the rear and vice-versa and we spent a lot of time coming in and out of the garage," said the Australian.
"It wasn't until the last half hour that we found something better and on my second-last exit I tried to push harder but ran off the track a little bit and destroyed the lap time. I decided to come in and have another go on a fresh tyre and if it wasn't for another rider in my way going into the last two corners I could have been on the front row.
"I'm disappointed in that respect but relatively happy with our pace in general. A few people are having problems with the front so it will be interesting to see what happens tomorrow, hopefully we can hang at the front.”