While either of the Nurgalieva twins - Olesya or Elena - is certain to win the Two Oceans Marathon women's title, the men's section is wide open.
Olesya is the defending champion after winning the 2008 edition of this Old Mutual-sponsored 56km ultra marathon scheduled for Saturday.
The Russian sisters have been dominating the Two Oceans, which forms part of their preparations for the Comrades Marathon where they have also been excelling.
The Two Oceans Marathon, which is known for attracting runners from as far as Russia, Germany and the US, is celebrating 40 years.
With Olesya leading a Russian clean sweep for the top four positions last year, it remains to be seen if the foreigners will continue monopolising the women's sections.
Irvette Van Blerk, who won the South African 10000m title and was second in the 5000m, will spearhead a strong South African contingent out to end the foreign domination.
Other South African women to watch out for include Carol Mercer (sixth), veteran Farwa Mentoor (seventh), Ursula Frans (eighth) and Leanne Juul (tenth) who were all among the top 10 finishers last year.
Turning to the men's section, defending champion Marco Mambo has emerged as the favourite. He is chasing his fourth title.
Previous champions from South Africa like Fusi Nhlapo, Sipho Ngomane, Bethuel Netshifhefhe, Simon Mphulanyane and Mluleki Nobanda are also reported to be in great condition.
Capetonian Mzwandile Maphekula, who was the first South African home last year after finishing second, is back to continue the chase.
Other locals capable of causing an upset include Simon Peu, Mabule Rapotle, Butiki Jantjies, Joseph Ikaneng, Peter Mathubi and debutant George Mofokeng.