Police constable Lai Hok-yan is determined to break his personal best time and win the US$15,000 prize on offer to the regional champions in Standard Chartered's Greatest Race on Earth series, which ends with the Hong Kong Marathon on Sunday. The series comprises four international marathons, with total prize money of US$1.57 million. Hong Kong are in a great position to clinch the first prize for national teams in the North East Asia region, after steady performances in the three legs so far. The SAR's accumulated time from the earlier legs is eight hours, 47 minutes, 22 seconds, which places them second in the regional challenge, just under 12 minutes behind Taiwan. Overall, Hong Kong are 17th out of 26 entries in the Nations Challenge. The Hong Kong Amateur Athletic Association (HKAAA) selected one runner for each of the three previous legs. Choi Tat-ming ran the first race (Nairobi) in a time of 2:59:49; Mo Wai-shing clocked 2:51:56 at the Singapore Marathon; and university student Lau Kwong-man completed the Mumbai event in 2:55:37. Lai, 33, will be the SAR's official representative at the Hong Kong Marathon. He will have to finish ahead of the Taiwanese competitor by more than 12 minutes for Hong Kong to grab the winners' purse. His personal best time of 2:35:42 was set during the 2004 Hong Kong Marathon. 'I'm going to do my best to break my own record and get the best result for the Hong Kong team,' said Lai. The Kenyans are the favourites to win the overall national team prize - US$70,000. The top team in each region will pocket US$15,000. Second place is worth US$7,500, and third US$2,500. In the main Team Challenge, the Run for Peace team have established a strong lead in the chase for the US$400,000 first prize. They are almost nine minutes in front of Team Akaki-Gianni. In the Individual Challenge, Kenyans Meshack Kirwa and Emmanuel Kosgei head to Hong Kong with just 18 seconds separating them from the top prize of US$100,000. In third place is another Kenyan, Stephen Ndungu. Team China will be led by Dai Yanyan, who is a formidable talent. She set her personal best of 2:24:00 at the 2001 Beijing Marathon, where she finished fourth.