British Superbike rider Chrissy Rouse has died after a crash at Donington Park at the weekend.
Organisers said the 26-year-old "passed away peacefully, surrounded by his family in hospital" on Thursday afternoon.
The Newcastle rider suffered a serious head injury after being unavoidably hit by a following rider on the first lap of Sunday's race.
Rouse was treated at the side of the track and taken to the circuit's medical centre, where he was put in a coma.
He later had emergency neurosurgery at a Nottingham hospital.
The race organiser MSVR said it was investigating the incident with the coroner, police and the Motorcycle Circuit Racing Control Board.
Rouse moved into British Superbikes this season and rode for Crowe Performance BMW, the same team he won the national superstock title with in 2020.
He was also a maths teacher.
Many well-known British bike racers have being paying tribute, including fellow British Superbikes competitors Tarran Mackenzie, Glenn Irwin and Peter Hickman.
Mackenzie tweeted: "This sport is so cruel sometimes. Talented in so many different ways and truly one of the nicest people in the paddock. RIP Chrissy."
Irwin, currently second in the standings, called him a "truly talented person" who was "always smiling", while Hickman said it was a "pleasure to know you and share a track with you, champ".
Rouse's death was announced on the same day British motorcycle racing also lost its most successful racer ever.
Phil Read MBE died peacefully in his sleep, aged 83, his son said.
Read won 52 grand prix in the 1960s and 1970s, and was world champion in the 125cc, 250cc and 500cc classes. He also won eight times at the Isle of Man TT races.