Jamaican sprint superstar Usain Bolt and British distance running icon Mo Farah end their glittering careers on the track as the world athletics world championships come to London for the first time. The Aug. 4 to Aug. 13 championships come five years after the athletics world gathered in the Olympic Stadium for the first time as the showcase sport of the 2012 Games. Bolt won another 100 meter/200m/4x100m treble and Farah got his first of now five straight big-event 5,000m/10,000m on the occasion in front of big and enthusiastic crowds that set a new standard for the sport. Now the two want to go out in style, with Bolt set to retire while Farah will concentrate on the marathon from next year onwards. Bolt, who turns 31 shortly after the championships, will only be competing in the 100m and relay. As in the past two years, he is yet to run really fast but has delivered when it mattered for an overall haul of eight Olympic golds and 11 world titles.

"My aim is to win in London. I want to retire on a winning note," Bolt said last week in Monaco. "I've accomplished all my goals. I've brought a different level of excitement and entertainment to the sport."

Bolt ran a season-best 9.95 seconds in Monaco, still 13-hundredths of a second shy of the season-best from American Christian Coleman but a confidence-booster.

"It was good, I'm going in the right direction, there's still a lot of work to do," he said.

Bolt will delight the fans with his usual pre- and post-race antics, and Farah also aims to produce his hands-to-head Mobot gesture two more times in front of a home crowd.

"I cannot wait for the championships. The preparation is going well, I am ticking all the boxes," Farah said last month after winning a Diamond League 3,000m race in the Olympic Stadium.

Other stars in what is a transitional year after the Rio 2016 Olympics include South African 400m world record holder Wayde van Niekerk, compatriot 800m Olympic champion Caster Semenya, Jamaican double Olympic sprint champion Elaine Thompson and American 400m holder Allyson Felix.

Some 2,000 athletes from more than 200 countries will be competing for 48 gold medals, with gender equality reached when the women have a first-ever 50km race walk on the closing day.

While the Russian federation remains banned in connection with doping allegations, a number of Russian athletes including title holders Sergey Shubenkov (110m hurdles) and Mariya Lasitskene (high jump) have been given the green light by ruling body IAAF to compete as neutral athletes. Athletics' new Integrity Unit will be responsible for a comprehensive anti-doping test program in London, which includes 600 blood tests already collected for the biological passports of the athletes and 600 urine samples to be taken to detect substances such as the blood booster EPO and steroids.