The relay world championships begin on 1 May in Silesia, Poland. Tokyo 2020 brings you the lowdown on the event, with Olympic qualification on the line.
Big names on the starting line
The stars are out in force for this weekend's World Athletics Relays (1-2 May), with big names including recently-crowned European indoor 400m champ Femke Bol of the Netherlands, Italy's European indoor 60m champion Marcell Jacobs and Colombia's world 400m silver medallist Anthony Zambrano signing up for the event.
From the African contingent, the continent's reigning 100m champion Akani Simbine (South Africa) and two-times African 100m champion Blessing Okagbare (Nigeria) make the journey to Poland, along with the youngest competitor at the event, Nigeria's Imaobong Nse Uko.
Hoping to make it a successful family affair, Belgium's Borlee brothers, Kevin, Dylan and Jonathan are raring to go in the men's 4x400m.
Tokyo 2020 hosts Japan have opted for a young team that includes Asian 4x400m champion Julian Jrummi Walsh as well as Remi Turuta and Rikuya Ito.
Italy will be able to count on Johanelis Herrera Abreu, Gloria Hooper, Anna Bongiorni and Irene Siragusa for the women's 4x100m event, while the Dutch team for the same event will feature an all-star lineup including two-time world champion Dafne Schippers, Jamile Samuel and Nadine Visser.
The USA have opted not to send a team to the championships due to the current situation with COVID-19, however reigning women's 4x400m champions, Poland will be hoping to take advantage of racing at home to retain their title.
(Photo by Matthias Hangst) 2019 Getty Images.
Tokyo 2020 spots up for grabs
One country that will be looking to secure Tokyo 2020 qualification is Japan, who have sent a 23-person team to the tournament. If they finish within the top eight teams in the men's 4x400m event, they will guarantee themselves an Olympic berth.
The names that have been tasked with securing qualification for their home Games are Kohsuke Ikeda, Kohei Itahana, Rikuya Ito, Kaito Kawabata, Kentaro Sato and Julian Jrummi Walsh.
The Czech Republic also have it all to play for in Silesia, as they currently sit in the final qualifying position for the Olympic Games. If they reach the final in Poland, they will book their tickets to the Olympics.
Unfortunately, one team that will miss out on the opportunity to qualify is India, who were recently forced to withdraw from the competition due to current travel restrictions.
(Photo by Matt Roberts) 2019 Getty Images.
Mixed relay teams with a chance to shine
As well as Tokyo quotas, the World Athletics Relays also offer teams the chance to get vital experience of the mixed relay format ahead of this summer's Olympic Games. The 4x400m mixed relay event will be making its debut in Tokyo after a successful introduction to major tournaments at the Doha 2019 World Championships.
The event involves teams of two women and two men, with each athlete running once around the athletics track before passing the baton onto the next runner. Because each team can choose whichever running order they prefer, tactics come to the fore, as seen in the World Athletics Championships final in Doha, where Poland chose a completely different strategy from the rest of the field.
In Doha, a USA team made up of Wilbert London, Allyson Felix, Courtney Okoloa and Michael Cherry won in a world record 3 minutes 9.34 seconds. They were followed home by Jamaica and Bahrain.
Mixed shuttle hurdles - an exciting battle to the finish line
Perhaps unfamiliar to many in the crowd, the mixed shuttle hurdles event is an exciting addition to the relay programme. The event involves teams of two men and two women competing together, with each athlete running a 110m leg. Women run their standard 100m hurdle leg with 10 metres extra running distance added to the end, while men run a standard male leg of 110m hurdles.
Unlike the mixed 4x400m relay, running orders are predetermined due to the different distances between hurdles men and women are used to competing with, and the additional 10-metre run women will be required to complete.
In the 2019 IAAF World Relays, the USA won gold in 55.09, followed by Jamaica in 55.47 and Japan in 56.13. The event will not be part of the programme for the Tokyo 2020 Olympic Games.
Find out when every race takes place in the World Athletics Relays schedule.