American sprinter Knighton runs 200m in 19.88 seconds, breaks Bolt's U20 world record

US' 17-year-old sprinter Erriyon Knighton has broken eight-time Olympic gold medallist Usain Bolt's Under-20 world record for the fastest 200-metre run. In the men's 200m semi-finals of the US Olympic trials, Erriyon ran 19.88 seconds to break Usain Bolt's U20 world record of 19.93 seconds. Erriyon turned professional in January earlier this year after turning 17.