Pedzisa mutsara unotevera: Kosgei akatanga basa rake renyika yose somumhanyi womucheto wenyika nomumhanyi womucheto. Akakurumbira semutambi wechidiki muna 1997 paakatora menduru yebronze yechidiki ku
1997 IAAF World Cross Country Championships, uye akasvikawo 1997 IAAF Grand Prix Final ye 3000 metres steeplechase. Akasimbisa mukurumbira wake nokugadza chinyorwa chenyika chevaduku chechiitiko chacho.