Rita Jeptoo's agent speaks on his athlete's failed drug test and discusses the depth of Kenya's doping problem.
Rock 'n' Roll Marathon Series elite athlete coordinator Matthew Turnbull reports from Sammy Wanjiru's home in Nyharuru, Kenya.
Manager confirms he died tragically Monday morning in Kenya.
Olympic champion says he has knee problems.
A challenging course and a tough field might not make it easy for the world's fastest marathoner.