British athletics legend Mo Farah will be looking for a morale-boosting performance in Sunday's Diamond League meet at the same London Stadium where he will bring down the curtain on his stellar track career in August.
The 34-year-old quadruple Olympic gold medallist -- who will focus on the marathon after the world championships which run from August 4th to 13th -- goes into the 3000 metres after a week in which documents leaked by Russian hackers Fancy Bears claim a sample he gave in 2015 had to be re-examined before being cleared in 2016.
Farah -- who is also a quadruple world champion at 5000 and 10000 metres -- hit back by saying he will never fail a test but the claims will cast a shadow over his appearance at the stadium where he lit up the London Olympic Games in 2012 with his triumphs in both the 5000 and 10000m.
"The meet is only four weeks before the World Championships so it will be a good chance to see where I am at and what fine tuning needs to be done," said Farah.
"A lot of the world's best athletes come to London for the meeting and it will be like a mini-World Championships in one day."
Certainly with more than 10 Olympic champions down to compete there is an air of a championships about it although aside from the men's 110 metres hurdles -- which features among others world record holder and 2012 Olympic champion Aries Merritt -- it is the women's events that are the more eyecatching.
Jamaica may be about to bid farewell to superstar Usain Bolt but in 2016 Olympic 100m and 200m gold medallist champion Elaine Thompson they look to have someone who will dominate the women's event as he has done the men's.
However, 2015 200m world champion Dafne Schippers -- who had to settle for silver in the 200m behind the Jamaican last year in Rio -- is hoping she can provide stiff opposition.
The 25-year-old Dutch athlete is keen to throw down the gauntlet over the shorter sprint distance and Sunday will give the 100m 2015 world silver medallist a chance to strike a psychological blow when she clashes with Thompson.
"Competing in the 100m at this event will be an important part of my preparation for the World Championships," said Schippers, who could finish only fifth in the Olympic 100m final.
"Looking at the names in the field, I think it will be a really exciting race."
Kendra Harrison will hope too to bring the crowd to their feet like she did last year when she set aside the disappointment of failing to make the American Olympic team by timing 12.20sec to break the 100m hurdles world record that had stood for nearly three decades.
This year she comes into the meeting having exorcised the demons of the American championships after winning the title and she believes she can go on and improve her record.
"This year I definitely think I can run another personal best, and that's what I plan on doing by the time the season ends," she told the Daily Telegraph.
Aside from the Diamond League events there will be an emotional farewell for Paralympian legend David Weir who won three golds in the stadium in 2012.
There will also be a medals ceremony which sees the British men's 4x400m relay team from the 2008 Beijing Olympics given bronze medals which they earned because the Russian team were disqualified for a doping offence.