Isaac Makwala will be given a chance to qualify for the IAAF World Championships 200 metres semi-finals at London Stadium on Wednesday, the sport's governing body has announced.
Makwala was pulled from the heats on Monday and withdrawn from the 400m final on Tuesday, with the IAAF imposing a 48-hour quarantine protocol recommended by Public Health England following an outbreak of gastroenteritis at a team hotel.
The 30-year-old was controversially denied entry to London Stadium for the 400m race, but he will still have a shot at the 200m - an event in which he is the world lead having clocked 19.77 seconds this year - after the IAAF accepted a request from the Botswanan federation for him to compete.
A statement from world athletics' governing body read: "The IAAF has received a written request from the Botswanan federation for Isaac Makwala to compete in the 200 metres.
"Given his quarantine period expired at 14:00 today (August 9) and following a medical examination which has declared him fit to compete, we have agreed under our existing rules that assuming he makes the qualification time, he will run in the 200m semi-final round this evening.
"Makwala is required to run a time of 20.53 [seconds] or faster to advance to the semi-finals. He will run at 18:40 this evening on his own in lane seven, which was his original lane draw in the opening round.
"No athletes already qualified for the semi-final will be adversely affected."
Earlier on Wednesday, Makwala had branded the IAAF's decision to withdraw him from the 400m as "sabotage", though the organisation claimed it was to avoid the spread of infection to other athletes.
Makwala was considered to be the leading contender in the 400m to challenge eventual gold medallist Wayde van Niekerk, who will take part in the 200m semis.