The 33-year-old Belgian's injuries were confirmed by x-rays in Spijkenisse, and he has been transported to the Maria Middelares hospital in Deurne.
His team's director Gino Verhasselt said that Amorison will undergo surgery tonight. "He sat next to me in the car in extreme pain. He could barely speak with his broken jaw.
"The fall itself didn't seem so bad, but the result certainly is. At the moment of the crash the peloton wasn't going very fast, and Amorison couldn't avoid a fallen rider. He instinctively tried to protect his head with his arm and broke two bones."
The team gave no estimate on how long Amorison, winner of this year's Vlaamse Pijl, would be out of action.