Ethiopian defeats rival Imane Merga.
Three nations could contend for the title in Poland.
Imane Merga and Tirunesh Dibaba headline the roster.
American Scott Bauhs finished a respectable fourth.
It will be Ethiopia versus Kenya in the men's and women's divisions.
Berlin Marathon winner Aberu Kebede was the women's champion.
Hiwot Ayalew won the women's race for an Ethiopian double.
It will be Ethiopia versus Kenya in Spain.
There were numerous world-class performances on the track Friday.