South African women's title holder Irvette van Blerk has withdrawn on the eve of the South African Half-Marathon Championships which will be run in Port Elizabeth on Saturday.
"Van Blerk injured her Achilles and decided that it would be better for her not to run in order to recover faster," Athletics South Africa said in a statement on Friday.
In her absence, 24-year-old Zintle Xiniwe, fresh off setting a 53:44 career best over 15km in Cape Town, has been touted as the woman to beat, along with versatile Rene Kalmer who recently recovered from a knee injury.
Defending men's champion Lucky Mohale will line-up as favourite in a bid for his second national road title this year.
Mohale won the SA 10km Championships with a gun-to-tape victory in Germiston in May.
Multiple national champion Stephen Mokoka is expected to provide Mohale with his stiffest challenge, despite focussing his training on the track in preparation for next month's World Athletics Championships in Daegu, South Korea.
Mohale and Mokoka face the likes of Xolisa Tyali, Mbongeni Ngxazozo and Boy Soke in what promises to be an intriguing battle in the men's race.