This is possibly the most difficult event to predict on the IAAF World Relays Yokohama 2019 programme.
PBs and season’s bests may give a rough indication of form over one lap of the track, but there’s no telling how athletes will fare when having to run two 400m legs in a relay in quick succession.
But the IAAF World Relays has never been an event that shies away from innovation and the 2x2x400m will be the first final to take place in Yokohama.
The minds behind this particular discipline felt it would play to the strengths of middle-distance specialists, given they would most likely be used to churning out speedy 400m repetitions off short recoveries in training.
If that turns out to be true, then the USA could start as favourites. Donavan Brazier is best known for setting continental U20 outdoor and senior indoor records at 800m, but he also possesses good 400m speed, as shown by his indoor PB of 46.91 set last year.
Teammate Ce’Aira Brown hasn’t contested a relay since her college days, but she has shown impressive form over a range of distances already this year, including an indoor 800m PB of 1:59.74 and a recent 1500m best of 4:07.68.
World and Olympic 800m finalist Ferguson Cheruiyot Rotich will be making his third World Relays appearance for Kenya. A 1:42.84 performer at best, he finished first in the 4x800m in 2014 and second in 2017. Emily Cherotich Tuei, who reduced her PB to 1:58.04 last year, is the other notable name on the Kenyan squad.
Fresh from a PB of 1:59.78, national 800m champion Catriona Bisset forms one half of a strong Australian duo. Joshua Ralph, who has PBs of 46.34 for 400m and 1:45.79 for 800m, will run the other two legs for Australia.
National 800m record-holder and six-time national champion Sho Kawamoto will be joined by national 800m champion Yume Kitamura on the Japanese team. Both have prior relay experience.
Alongside the host nation, the Athlete Refugee Team will be sure to draw big cheers from the crowd. They will be represented in this event by James Nyang Chiengjiek and Rose Nathike Lokonyen. They competed at the 2016 Olympic Games in the 400m and 800m respectively. Lokonyen also competed at the IAAF World Championships London 2017, but this will be Chiengjiek’s debut at an IAAF World Athletics Series event.
Belarus, with 2015 world 800m champion Marina Arzamasova, and Poland could also feature among the top teams in this discipline.
But until the athletes enter the final straight on their second legs, there’s no telling what will happen.
Jon Mulkeen for the IAAF