Bernard Koech will lead a strong Kenyan contingent for the Tokyo Marathon this Sunday.
Koech, who has a personal best of 2:04:09 set at the Amsterdam Marathon in 2021, where he finished second.
He will have Titus Kipruto, who has a personal best of 2:04:54 set at the Amsterdam marathon last year, for company.
Kenya's Mike Kipruto Boit, Brimin Misoi and Vincent Raimoi are also contenders for the title.
The Kenyan quarter will, however, face a stern test from 2021 London Marathon champion Sisay Lemma of Ethiopia.
Lemma won the London Marathon in 2:04:01 and will have compatriots Tsegaye Getachew, Mohamed Esa, and Deme Tadu Abate for the company as he seeks to add another feather to his hat.
Getachew has a personal best of 2:04:49 posted while winning the Amsterdam Marathon last year while Esa's PB is 2:05:05 recorded while placing fifth in Amsterdam in 2022. Abate's PB of 2:06:28 was achieved in Berlin, where he placed third last year.
Japan had entered the last three national record holders, Kengo Suzuki, Suguru Osako and Yuta Shitara but the withdrawal of Suzuki last month leaves two to battle for the honours.
Osako is the fastest Japanese man in the field with a 2:05:29 set in Tokyo three years ago.
Hidekazu Hijikata, Kyohei Hosoya, Ryu Takaku and Hiroto Inoue have all run 2:06 and another nine Japanese men on the list have run 2:07.
At the pre-race press conference, Japan's most consistent marathoner over the last few years, Hosoya said he is in great shape and will be going for the Japanese NR and at a minimum the top Japanese spot.
In the women's category, Rosemary Wanjiru will spearhead Kenya's quest for glory in the Japanese capital.
Wanjiru has a personal best of 2:18:00 posted when she finished second in the Berlin Marathon last year.
She will have fellow Kenyan and 2022 Toronto Marathon champion Antonina Kwambai for the company. Another Kenyan Betsy Saina will be among the athletes to watch. Saina is back from maternity leave and ran a promising 1:08:25 for the win at the Seville Half Marathon earlier this year.
Ashete Bekere of Ethiopia is the race favourite with a personal best time of 2:17:58 when finishing second at the event in 2021.
Others to look out for the title include compatriots Tigist Abaychew and Worknesh Edesa.