Pedzisa mutsara unotevera: Osoro akamiririra Kenya kaviri pachikuva chenyika muna 1991, achimhanya ku
1991 IAAF World Cross Country Championships (kwaakauya wechishanu mumakwikwi akareba) uyezve panzira pa1991 World Championships muAthletics (achibviswa mumakwikwi emamita zviuru zvishanu nemuganhu mudiki kuna Dionísio Castro). Zvisinei, akahwina menduru mumakwikwi emamita zviuru zvishanu mumutambo weAll-Africa Games wegore iroro ra1991. Akaratidza muKenya World Cross Country chikwata kechipiri panguva 1992 IAAF World Cross Country Championships, kunyange zvazvo akanga zvishoma akabudirira kuedza ichi sezvo akapedza panzvimbo 23. Pakati pekubuda kwake mudunhu, akakunda muBelfast International Cross Country meet.