Chavanel, 38, won the overall title of the French 2.1 race in 2005, 2006, 2014, and 2016, the latter two coming courtesy of victory in the time trial stage. This time, however, he was unable to start the time trial on Thursday afternoon as he crashed in the morning road stage, having started the day sixth overall.
The crash occurred on one of the sections of dirt road that had been included in the final 20km of the short stage and it appeared that Chavanel had come off pretty lightly as he remounted and completed the stage, finishing in 51st place in a group just 34 seconds down on the main pack.
However, he was taken to hospital in Poitiers, where scans revealed a double fracture of his left scaphoid bone, and was forced to abandon the race.
"I had the legs but not the hand," Chavanel wrote on Twitter, indicating that he would be out for four weeks.