Tinkoff-Saxo have demanded an apology from Vuelta a Espana organisers and called for the UCI to review rules after their top sprinter, Peter Sagan, was hit by a motorbike at high speed causing him second degree burns and forcing him to abandon the tour.

The Slovak rider, who won his fourth Tour de France green jersey in succession in July and was in contention for his first in the Vuelta, was accidentally hit by a neutral service bike weaving through a group of riders during stage eight on Sunday. Sagan was left with cuts and burns to the left side of his body as well as a contusion on his left arm.

Sagan was livid and was seen kicking his bike and another motorbike. He was later fined for abusive language and received a separate fine for “behaviour that damages the image of cycling”.

Lightning struck twice for Saxo Tinkoff during Wednesday’s 11th stage when a second of their riders, Sergio Paulinho, was forced to withdraw from the race after colliding with a TV motorcycle.

The Portuguese rider was taken to hospital and needed 17 stitches in his leg.

In an open letter addressed to the event organiser, Unipublic, and Brian Cookson, the president of the UCI, Tinkoff-Saxo wrote: "The facts are clear and beyond discussion: the driver of the motorcycle carelessly and improperly tried to overtake the reduced peloton at very high speed about 8km from the finish line apparently in an attempt to reach the leading three riders a few seconds in front."

The letter requested a list of five actions: an apology from Unipublic; a donation to charity from Unipublic equal to the value of the green jersey; measures taken to prevent a future incident; Sagan’s fine for damaging the image of cycling to be revoked; and the UCI to initiate a review of the rules of “the admission to vehicles’ drivers inside the race? with the intent of implementing appropriate rules changes no later than the start of the 2016 race season.”

The statement added: “It is clear that the driver should not have performed the overtaking of the peloton and – at a minimum – he failed to use adequate care in his attempt. The crash at high speed could have had much more severe consequences for the rider who was defenceless against such an action by the motorcycle’s driver.”

Sagan said after the incident: “I didn’t even hear the motorbike coming. I find it unacceptable that a motorbike tries to weave its way into the group at such high speed.

“They accelerate and try to sneak in when they see an empty space. However, they don’t take into consideration that a rider might fall in front of them or change direction. They go extremely fast and the difference of speed compared to the riders is enormous.”

Kris Boeckmans, who was injured during the same stage when he crashed while taking a drink, is to remain in an induced coma for several more days. The Lotto-Soudal rider suffered broken ribs and facial fractures as well as an injury to his lung causing the need for breathing assistance, but is reportedly in a stable condition.

Spain’s Mikel Landa won the 11th stage of the Vuelta on Wednesday and his Astana Pro team-mate Fabio Aru became the new race leader as Chris Froome crashed before coming home 15th.

The 25-year-old Landa (Astana Pro Team) clinched the 138-kilometre route from Andorra la Vella to Cortals d’Encamp, the toughest stage to ever feature in the Vuelta, in four hours, 34 minutes and 54 seconds.

Italy’s Aru crossed the line one minute and 22 seconds behind to finish second while American rider Ian Boswell of Team Sky came in third.

Team Sky rider and 2015 Tour de France winner Froome crashed on the first climb of the stage and – despite suffering a cut to his right leg – he was able to finish the highly-demanding stage, which contained six mountain passes.

He ended 15th, seven minutes and 30 seconds behind Aru, and has dropped to 15th overall, seven minutes and 30 seconds behind the new red jersey.

Aru was handed the race leader’s red jersey and leads the general standings, 27 seconds ahead of Spain’s Joaquim Rodriguez (Team Katusha), who came home 1:59 behind the stage winner.

Giant-Alpecin’s Tom Dumoulin, who went into Wednesday’s stage as the race leader after Tuesday’s rest day, has dropped to third in the general standings and the Dutchman is now 30 seconds adrift of Aru.

Nicolas Roche ws another to lose serious ground, dropping from fourth position to 22nd after coming home in 52 positions, 14 minutes and 25 seconds behind the stage winner Landa.

(Guardian service)