Shitara Yuta and Inoue Hiroto will be in hot pursuit of Japan record-holder Osako Suguru and the last ticket to the 2020 Tokyo Olympic Games in Sunday's (1 March) Tokyo Marathon.
Going into the race with a field of 192, Osako is currently the closest of the three to the Games after finishing third in the Marathon Grand Championship in September.
Shogo Nakamura and Yuta Hattori finished one-two in the MGC to sew up the first two spots for Tokyo 2020.
Osako in driver's seat
For either ex-Japan record-holder Shitara and 2018 Asian Games gold medallist Inoue to unseat Osako for the third and final berth at the Tokyo Olympic Games, he must be the highest Japanese finisher in Sunday's race - and break Osako's mark of 2 hours, 5 minutes, 50 seconds in the process.
The Lake Biwa Marathon next weekend technically is also a Tokyo 2020 qualifier, but the Tokyo Marathon is the de facto showdown ahead of this summer's Games.
Osako certainly has the edge in the qualifying scheme yet never had any intention of resting on his laurels. He trained in Kenya for this race, pushing himself harder than ever.
"I just need to run at my own pace. The record is mine and when you consider the weather forecast, race conditions, it's not a stretch for me to break my own record", Osako said at a press conference Friday.
"I practised in Kenya. I wasn't doing anything differently but managed to put in some quality training time. It's the same with all the other races, I'm only thinking about running faster than everyone else.
"As I always say, the fight is within me".
Regaining the edge
Shitara held the old national record at 2:06:11 before Osako rewrote it in Chicago two years ago, and is keen to recapture the bragging rights on Sunday.
"I'm hoping to run the way I'm capable of running", Shitara said. "I've been practising well and feel like I'm in pretty good condition. If I can keep up with the foreign runners, I should be fine.
"I don't want to overthink, just let the race come to me".
This year's Tokyo Marathon will feature only the elite runners - including 14 from overseas.
Following the outbreak of the coronavirus organisers said in a statement on 17 February: "We have been preparing for the Tokyo Marathon 2020 while implementing preventive safety measures.
"However, now that case of COVID-19 has been confirmed within Tokyo, we cannot continue to launch the event within the scale we originally anticipated".
The race will be held on the course laid out previously for the Games' marathon before it was moved to Sapporo last year. The race record is 2:03:58.
The defending men's and women's champions from Ethiopia, Birhanu Legese and Ruti Aga, have returned. The two have the fastest times in the field, Legese with a personal best of 2:02:48 and Aga 2:18:34.
The final female Japanese for the Tokyo 2020 marathon will be decided on 8 March at the Nagoya Women's Marathon. Maeda Honami and Suzuki Ayuko placed first and second in the MGC, respectively, to qualify for the Games.
The Tokyo Olympic women's marathon will be held on 8 August with the men's race the following day.