Movistar's Spanish cyclist Alejandro Valverde

Slovakian rider Peter Sagan has become the latest high-profile withdrawal from Spain's Vuelta after being hit by an auxiliary motorcycle during Saturday's eighth stage.

Sagan, who had ended a two-year drought without a Grand Tour win on stage three, looked set to challenge for another stage victory and held the green points jersey until the incident took place just over eight kilometres from the finish.

"Tinkoff-Saxo announces that, unfortunately, the team's co-leader at the Vuelta a Espana cannot safely continue to race and will instead return home to recover," the Russian team said in a statement on Sunday.

"Sagan was hit by a reckless auxiliary motorbike in the final kilometres of stage eight and suffered wounds and burns of first and second degree on the left side of his body, from the hip to the lower leg. In addition, he has a contusion on his left forearm with an intra-muscular haematoma."

Tinkoff-Saxo also said on Saturday that they would explore taking legal action against the parties that caused the crash.

"Unfortunately, it isn't the first time such an incident happens," said Sagan.

"Even if motorbikes are forced to go through a group of riders, they should do it very carefully and not recklessly. In my opinion, motorbike drivers don't take the safety of the riders in consideration seriously."

Sagan's withdrawal is just the latest in a number of big names to exit the race after a crash-dominated stage from Puebla de Don Fadrique to Murcia.

Belgian rider Kris Boeckmans has been placed in an induced coma after a major pile-up 50 kilometres from the finish.

Ireland's Dan Martin, who had been lying third in the general classification, American Tejay van Garderen and France's Nacer Bouhanni were also forced to abandon after being caught up in the same crash.

Saturday's stage winner Jasper Stuyven was also forced to withdraw after he claimed his first Grand Tour victory despite breaking a bone in his wrist.