San Sebastian, Spain (AFP) – Julian Alaphilippe, the winner of the polka dot jersey for the best climber at the Tour de France, pipped Bauke Mollema to victory in a sprint finish at Saturday's San Sebastian Classic.

Quick Step rider Alaphilippe and Mollema, the 2016 champion, broke clear with eight of the 228.7 kilometres remaining in Spain after a nasty crash sent two race favourites, Egan Bernal and Mikel Landa, to hospital.

The pair were caught up in a multi-rider pile-up around 20km from the finish, with Colombian Bernal suffering "a serious facial trauma." 

"He is awake and talking. He has had a precautionary scan to assess for further injuries which revealed a nasal fracture and maxillary injury," Team Sky said in a statement.

The 21-year-old will remain in hospital overnight for observation and further treatment.

Movistar said Landa was left in "huge pain" with a sore back and placed in an immobilising brace. He was set to undergo exams to determine the extent of his injuries.

The 26-year-old Alaphilippe continued the good form that saw him win a pair of mountain stages on this year's Tour and easily claim the king of the mountains prize.

Saturday's race favoured the climbers, with eight climbs in total including a double ascent of the category one Jaizkibel.

Alaphilippe and Mollema escaped on the day's final climb, the Murgil Tontorra which featured sections with a gradient of 22 percent, before the Frenchman shone again in a two-man sprint.

"I've had a good season," said Alaphilippe. "I was well placed for this sprint. I waited until the last moment because I knew the climb was very difficult and when Mollema decided to go for it I followed him."

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