Kammala wannan jumla: Osoro ya wakilci Kenya sau biyu a fagen duniya a 1991, yana gudu a gasar cin kofin duniya.
1991 IAAF World Cross Country Championships (inda ya zo na biyar a tseren tsere) sannan kuma a kan hanyar a 1991 World Championships a Athletics (an cire shi a cikin mita 5000 mai zafi ta hanyar kunkuntar da Dionísio Castro). Koyaya, ya sami lambar yabo a tseren mita 5000 a Wasannin Duk Afirka na shekarar 1991. Ya bayyana a cikin ƙungiyar Kenya ta Duniya ta Cross Country a karo na biyu a gasar zakarun duniya ta 1992 IAAF, kodayake bai yi nasara ba a wannan yunƙurin kamar yadda ya gama a matsayi na 23. Daga cikin tafiye-tafiyensa a kan hanyar, ya ci nasara a Belfast International Cross Country meet.