However, Australian hurdler Sally Pearson, American high jumper Brigetta Barrett and sprinter Justin Gatlin did not shy away from discussing the issue of doping on Thursday.
"You have to make sure that you're responsible for what's going into your body and who's around you," said Gatlin, a former Olympic and world champion who was suspended for four years after testing positive for a banned substance in 2006.
"It's just life. That's one thing I learnt when everything happened with me" Gatlin said. "You got to deal with it. You got to move forward. The one thing I learnt about track and field is: It's not about what you say, it's about what you do."
Gay will turn 31 in August. If his 'B' sample also proves positive, he could face a two-year ban and would struggle to be competitive again.
"Getting back in shape was really the toughest part," Gatlin recalled. "I came back like 20 pounds overweight."
Barrett, who won the U.S. trials with a personal best of 2.04 and is the Olympic runner-up, clearly hadn't expected the string of doping test announcements in recent weeks.
"You're always shocked by the news when your 'heroes' have fallen," Barrett said. "It does feel like a shock because I didn't expect those people to have a positive test.
"As far as Tyson Gay is concerned, my heart and my prayers go out to him and anybody else having to deal with the consequences of a positive test result," added Barrett. "And I can only pray that they could deal with it with grace and that other people can treat them accordingly."
Pearson regretted that doping has returned to plague the sport's image, but highlighted the work of anti-doping authorities around the world.
"It's disappointing that these things happen," she said. "But at the same time, I guess it's good that whatever doping agency is doing it is keeping on top of the athletes.
"It's a shame that you have to talk about it. It's a shame that you have to comment on it and have a feeling and an opinion about what's happened, because it's hard. We know these athletes personally as well. It can be difficult."
As for the meet, though, there should be plenty of action on the night.
Gatlin will face the new generation of Jamaican sprinters with Kemar Bailey-Cole and Nickel Ashmeade, who respectively finished second and third behind Usain Bolt at their national trials in Kingston.
European champion Christophe Lemaitre of France pulled out of the meet to focus on training while Bolt skipped the Diamond League event.
Gatlin edged Bolt by 0.01 second in Rome last month to be the only sprinter who has beaten the six-time Olympic champion this season.
"I feel like I'm No. 1, that's my thought," Gatlin said with a grin. "My mum thinks I'm the No. 1."
Gatlin will be Bolt's main rival in the 100 at the Moscow worlds, which start on Aug. 10.
In the men's triple jump, Olympic and world champion Christian Taylor competes against Pedro Pichardo of Cuba. Picardo is only 20 but he's the 2012 junior world champion and leaped a world-leading 17.69 in Havana last month.
Barrett will be up against two veterans, Olympic champion Anna Chicherova of Russia and two-time world champion Blanka Vlasic of Croatia in Monaco.
In the women's 100 hurdles, Olympic and world champion Pearson will compete against Kellie Wells of the United States, who finished third last year in London. Brianna Rollins, who set a world-leading time of 12.26 at the U.S. trials, and heptathlon Olympic champion Jessica Ennis of Britain both pulled out.
The Herculis meeting is the 10th leg of the Diamond League.
- AP