Nicky Hayden dead: Former MotoGP world champion dies aged 35 after cycling crash in Italy

The 35-year-old American was involved in a road accident while training along the Rimini coastline

Nicky Hayden became the MotoGP world champion in 2006 (Getty)

Nicky Hayden, the World Superbike Championship rider and 2006 MotoGP world champion, has died five days after being involved in a road collision.

The 35-year-old American was cycling along the Rimini coastline in Italy last Wednesday when a car collided with his bicycle.

Hayden, from Owensboro, Kentucky, suffered head and chest injuries in the collision and was transferred to the Maurizio Bufalini Hospital in Cesena, where he was treated in the intensive care unit.

The Red Bull Honda rider was training in Italy following his 12th-placed finish in the World Superbike Championship race at Imola on 14 May. Members of the rider's family, including his mother Rose and brother Tommy, had flown out from the United States to be beside him during his time in hospital.

His death was announced by the Cesena hospital on Monday afternoon, with doctors explaining that Hayden had suffered “a serious polytrauma” following the accident.

The hospital's statement read: “The medical team has verified the death of the patient Nicholas Patrick Hayden, who has been undergoing care since last Wednesday 17 May in the intensive care unit of the Bufalini Hospital in Cesena following a very serious polytrauma which occurred the same day.”

Hayden upset the odds to claim the 2006 MotoGP championship in one of the most entertaining seasons in recent memory, edging Valentino Rossi to the title to end the Italian's five-year streak of wins

After news of Hayden's accident broke last week, Rossi paid tribute to his competitor and described him as “one of the best friends I've ever had in the paddock”. Dani Pedrosa, Hayden's team-mate in 2006 when he won the world title, posted a photo of the American on his Twitter account, writing: "Always in my heart, champ. RIP Nicky. #69."

The 2006 victory would be Hayden's only championship, but 'The Kentucky Kid' remained in MotoGP until 2015. The following year, he switched to the World Superbike Championship and finished fifth in the overall standings, winning that year's race in Malaysia.

Hayden held 13th place in the current season's standings following last Sunday's race at Imola.