SAPPORO, Japan (Reuters) - Japan may have come away without a medal as it hosted the latest Olympic marathons but can take heart in the high finishes of its top runners in hot and humid conditions that forced many of the world's top competitors to drop out.

Suguru Osako finished sixth in the men's marathon on a humid and windy Sunday in Sapporo when 29 runners exited the race early including world champion Lelisa Desisa of Ethiopia and 2012 Olympic gold medallist Stephen Kiprotich of Uganda.