Chris Froome suffered a scare in the defence of his Tour de France title after crashing during stage four before recovery to remain in contention for the general classification.
Marcel Kittel won his third stage of the tour in a sprint finish in Lille, ahead of Alexander Kristoff and Arnaud Demare.
The Team Sky rider crashed within minutes of the fourth stage starting, the first on the French mainland following the Grand Depart from the United Kingdom, before receiving lengthy treatment on hip, elbow and shoulder cuts.
Froome, who fell in similar fashion during last month's Criterium du Dauphine was also treated for a wrist problem which he initially sustained in Switzerland, and the injuries suffered on day four could be significant ahead of the cobbled stage starting in Ypres.
The Briton remains two seconds behind yellow jersey holder Vincenso Nibali after four stages, but the withdrawal of Greg Henderson with a similar fall, emphasises how close Froome's own campaign was to ending prematurely.