After setting a world record in the semi-final, the Australian was expected to win gold 24 hours later.

It's a situation Emma McKeon will experience on Friday morning, the Wollongong star to line up as favourite for the blue-ribbon event in Tokyo.

Read more: Silver lining for Chalmers at Tokyo

After setting an Olympic record in the heat, the 27-year-old cruised through Thursday's semi-finals to book her place in lane four for the gold-medal race.

Henry handled the pressure, becoming the first Australian to win the event since Dawn Fraser in 1964.

When McKeon stands behind the blocks on Friday, Henry will be one of few people to understand her emotions in that moment.

"Breaking the world record did change things for me," Henry said. "I did have to manage it and had to do a couple of things to manage those nerves.

"I can empathise with the Campbell sisters in Rio, the expectations they had. There's no doubt going in the fastest to an Olympic final adds expectations. I'm just in awe of the current athletes and what they're dealing with right now."

McKeon enters the final after winning her third medal of the Games on Thursday, bronze in the 4x200m freestyle relay.

The event was one Australia were considered favourites, however they were defeated by a brilliant Chinese outfit, with America second.

McKeon will have to put that disappointment behind her as she looks to become just the fourth Australian to win the women's 100m freestyle event and the first since Henry's triumph in 2004.

Before that, it was Fraser who claimed three-straight Olympic gold medals from 1956 to 1964 and Fanny Durack back in 1912.

Some of Australia's greatest swimmers have fallen short, including Shane Gould and Libby Trickett.

The latest to miss gold was Cate Campbell, after she started heavy favourite only to finish sixth in Rio.

The four-time Olympian has a shot at redemption on Friday, Campbell to line up alongside McKeon.

Shannon Rollason was the mastermind behind Henry's victory in Athens and he said McKeon and Campbell have done the work. Now it's down to mental preparation.

"It's the biggest race at the Olympics," Rollason said. "It's the blue ribbon event. It's like the 100m on the track, it doesn't get any bigger than that. That's why it's so hard to win, why many a person who's been world champion or world record holder, that gold medal can elude them.

"The key is the mental side of it. Not getting ahead of yourself, not celebrating good swims. At the end of the day, they don't hand out the medal in the heats or semi. Even if you break the world record, they still don't give you a medal until you do it in the final."

McKeon and Campbell are looking to continue a golden run for Australia in the water, with Zac Stubblety-Cook taking out the 200m breaststroke final on Thursday.

The 22-year-old win came as Kyle Chalmers fell millimetres short of defending his 100m freestyle title, the South Australian second behind Caeleb Dressel.

Later on Thursday, Jess Fox rebounded from Tuesday's disappointment to win gold in the women's C1 canoe slalom.