The mixed 4x400m relay at the IAAF World Youth Championships, Cali 2015 (Getty Images) © Copyright
Preview Nairobi, Kenya

Preview: mixed relay – IAAF World U18 Championships Nairobi 2017

Closing out the biennial championships as the last track event on show, 16 teams will turn out for a place in the final of the mixed 4x400m, which tests each nation's depth across the board in the 400m sprint.

South Africa will be the only medallists from the previous edition of the showpiece in Cali two years ago who return to compete for the title, and they will be led by hurdles star Sokwakhana Zazini, an accomplished athlete in his own right in the flat one-lap sprint who boasts a 46.20 personal best.

Jamaica, however, is represented by a superb team and could turn out as the favourites for the gold medal.

They will be carried by a powerful quartet which is expected to include two of the fastest 400m boys in the world this year – Anthony Cox and Antonio Watson – as well as Shaquena Foote, one of the main contenders for the individual girls' title.

Wesley Botton for the IAAF