GENEVA—Two-time Olympic 800-meter champion David Rudisha will not defend his title at the Tokyo Games. Rudisha’s agent, Michel Boeting, told The Associated Press on Thursday that Tokyo was “out of the question” for Rudisha because of a persistent hamstring problem. The Olympics are set to open on July 23 and the 800 heats start July 31. “He is just contemplating his next step, whether it’s retirement or to continue training,” Boeting said in a telephone interview. Now 32, Rudisha has not run at the international level since the 2017 season, and the current injury is linked to chronic inflammation of his sitting bone, Boeting said. Rudisha set the world record of 1 minute, 40.91 seconds when he won gold at the 2012 London Olympics. No one has since come within a second of that time. The Kenyan retained his title in Rio de Janeiro, in 1:42.15, and also has two …