<prompt> Feleletša polelo ye e latelago: Kostitsyn o ile a dira ponagalo ya gagwe ya bobedi ya ka tlase ga nywaga e 20 go  <response>: 2002 World Junior Ice Hockey Championships gomme o ile a raloka dipakane tše tharo go thuša Belarus go dula ka sehlopheng se se phagamego. Ka morago ngwageng wona woo, Kostitsyn o ile a boela sehlopheng se se phagamego ka 2002 IIHF World U18 Championships, a rekota dintlha tše 10 ka dipapading tše seswai gomme a thuša Belarus go fihla maemong a bohlano. Ge a be a phadišana ka phadišanong ya gagwe ya boraro ya ka tlase ga nywaga e 20 ka 2003 World Junior Ice Hockey Championships, Kostitsyn o ile a rekota diphadišano tše pedi le go thuša go tee, eupša o ile a theošwa le Belarus go Division-I ka 2004. Ge a be a bapala sehlopheng sa maemo a bobedi, o ile a thopa dipakane tše hlano le dintlha tše 10 ka dipapading tše hlano go thuša Belarus go boela sehlopheng sa maemo a godimo ka 2005, moo a ilego a thopa dintlha tše hlano ka papading ya gagwe ya bohlano le ya mafelelo ya World Juniors. 