World Indoor Athletics Championships: 400m heat sees all athletes disqualified

Grenada's Bralon Taplin has fronted an historic first at the World Indoor Athletics Championships in Birmingham.

The 400m favourite won his heat in 46.37 seconds, the fastest time in the world this year, but all athletes in the heat were later disqualified.

Qatar's Abdalleleh Haroun was ruled out for a false start before the four other athletes ran out of their lane.

BBC statistician Mark Butler says the disqualification of a full field had never happened before in athletics.

"All of these athletes and their countries can appeal, so we may see some of them come back," said BBC Sport analyst Michael Johnson.

In indoor 400m competition, athletes can leave their lane after passing a break line.

But Taplin, Austris Karpinskis of Latvia, Bahamian Alonzo Russell and Jamaica's Steven Gayle were all deemed to be guilty of lane infringements before the line.

Their omission from the event has aided other athletes, as two additional qualification spots were allotted to fastest losers from the other five heats.

The men's 400m semi-finals take place at 21:06 GMT, live on BBC Red Button and the BBC Sport website.