Olympic champion Karsten Warholm runs the 4th fastest time in history for the men's 400m hurdles in Oslo, setting the Diamond league record #NBCSports #TrackandField #KarstenWarholm » Subscribe to NBC Sports: youtube.com/nbcsports » Watch Live Sports on NBCSports.com: nbcsports.com/live NBC Sports Group serves sports fans 24/7 with premier live events, insightful studio shows, and compelling original programming. NBC Sports is an established leader in the sports media landscape with an unparalleled collection of sports properties that include the Olympics, NFL, Premier League, NASCAR, PGA TOUR, the Kentucky Derby, Tour de France, French Open, IndyCar and many more. Subscribe to our channel for the latest sporting news and highlights! Visit NBC Sports: nbcsports.com Find Premier League on NBC Sports: nbcsports.com/soccer/premier-league Find NASCAR on NBC Sports: nbcsports.com/motors/nascar Find Sunday Night Football on NBC ...