Kirui will test his form in Saturday's Prague Half Marathon as he targets a future marathon win.
Kenyan Gladys Cherono takes the women's race.
Zersenay Tadese will fight the temperatures as much as his competitors.
World record holder could better his mark next week.
He needs to run faster than 58:23.
Atsedu Tsegay, Joyce Chepkirui shatter the previous marks.
The 24-year-old Kenyan road-running ace is ill.
It was the first sub-1 hour half on Czech soil.
The British runner quit his job to run for charity.