Simone Biles has already pulled off a vault at Tokyo 2020 so difficult that no other woman has ever tried it at the Olympics - before she even starts her bid for gold.
The American gymnastics star twice attempted the Yurchenko Double Pike vault at podium training earlier, the second of which she almost perfectly landed. Biles first performed the move in April - becoming the first to give it a go in competition.
If she attempts the skill in Tokyo, the move will be named after Biles - but it is not known yet whether the 24-year-old will try it, given she already dominates the sport and may not need to pull something off which is quite so tricky.
Hayward: Hot inside, ice-cold outside, Whitlock shows champion mentality, and he's not done yet
"I didn't think she was going to do the double pike today," coach Annie Diluzio said.
"Then she came out and did it and I was just as shocked as everybody else. If she does it like that, we could see it in competition, I'm not sure when."
- Biles ‘one of the best gymnasts ever’ - Whitlock
- Tokyo 2020 Olympic Games: Schedule, key events, every medal and more
Biles won four gold medals at Rio 2016 and she goes into the all-around competition having never lost that event at any championship since 2013.
Biles on 'living in the moment' in Tokyo
One of her main coaches, Laurent Landi, recently said that it may be unlikely Biles will try the difficult move at the Olympics - so it is possible we have seen it for the last time in Tokyo already.
"If she really wants to do it, she’s going to have to beg me,” Landi told NBC’s On Her Turf last week.
“People seem to forget that it’s a very, very dangerous skill… Just to have glory and being [in] the Code of Points, it’s not enough.”
Watch every unmissable moment live from Tokyo 2020 across Eurosport, the Eurosport app and discovery+. Download the Eurosport app for iOS and Android now.
'That's the most nervous I've ever been' - Whitlock on winning routine
'The most nervous I've ever been' - Whitlock describes Pommel Horse pressure