Mikel Landa breaks his right collarbone and two ribs and joins the large list of injured in the Basque event. Frenchman Romain Grégoire, 21, won the fifth stage in Amorebieta.
The Itzulia will be decided on Saturday at the arrival in Éibar, also betrayed by the traditional climb to Arrate. It could be a duel reminiscent of the last Tour of Switzerland between the leader, the Dane Mattias Skjelmose, and the Spanish Juan Ayuso.