It was a scenario that confronted Perkins in Atlanta in 1996, having taken gold in the 1500m in Barcelona four years earlier.
While Chalmers has endured a disrupted preparation for Tokyo courtesy of the raging pandemic that all athletes are dealing with, Perkins had a nightmare lead-up of his own making for the 1996 Games.
He missed selection for the 400m freestyle, despite being the reigning world record holder and silver medallist from 1992. While he made the team for the 1500m, he struggled so badly in the Atlanta Games heats he only made it into the final as the eighth-fastest qualifier.
In a swim that has been etched into Olympics folklore, Perkins, from lane eight, produced a comeback of Lazarus proportions to take the gold medal, leading home Daniel Kowalski in an Australian 1-2.
Now the president of Swimming Australia, Perkins said his mindset in defending a title had been far removed from four years earlier in Barcelona.
“It’s a very different experience. You’ll hear this from athletes in any sport, but the big difference is the first one is much easier than the second or third,” he told Wide World of Sports.
“The more you have to defend, the harder and harder it gets.
“When you’re the hunter you’ve got something to aim for, something to pursue, benchmarks to reach and break through. When you’re the leader, it can be easy to lose focus and direction.”
Olympics dreams are made or shattered by the barest of margins. Had Perkins’ heat time of 15:21.42 been just a quarter of a second slower, he would have missed the Atlanta final altogether, with Germany’s Steffen Zesner lining up in lane eight instead.
“At the Olympic level, the difference between a gold medal and not making the final is measured in milliseconds,” Perkins explained.
“I certainly went through it, and you see a lot of other athletes go through it as well. I think where it’s more acutely obvious is the fact the Olympics are once every four years, or five years in this case.
“There’s plenty of great athletes who compete in sports where they have annual opportunities, they get the feedback very quickly if they’re losing direction.
“But you can lose a year or two in an Olympic preparation without getting that reminder to get your head down.”
Losing direction is something Perkins is very conscious of. He attributes his struggles in the lead-up to Atlanta to a loss of focus as far back as 1994.
“Coming out of the 1994 world championships and Commonwealth Games, I started thinking solely about the Olympic final in 1996,” he said.
“In the lead-up to pretty much every meet before then, every day, every week, every month, I had a meet or some level of competition to focus on.
“Then I had a two-year gap to Atlanta. I started focusing on this final that was in the distant future, as opposed to today and what I needed to do right now.
“As a consequence, I just wasn’t working at the same level of intensity that I had previously.”
Perkins explains that the difficulty of remaining focused on the Olympics has been magnified this time around, following the 12-month delay caused by the COVID-19 pandemic.
At the start of 2020, the Games were just six months away, before the decision was taken to postpone them until 2021.
The dual Olympic gold medallist noted that those who haven’t been fazed by disruptions and setbacks will likely shine in Tokyo.
“You’ve got to be able to focus on what you can control,” he said.
“Our athletes in Tokyo will be tested regularly and wearing masks all the time, they’re going to have to engage in a process that is very different to what an Olympics would normally be like.
“You can get frustrated and annoyed by that and allow it to disrupt you, or you can accept it, recognise that it is what it is, and focus on what you can do to manage it.
“When you’ve got eight finalists standing on the blocks for an Olympic final, how they’ve handled the disruptions will be a significant defining factor between the winner and the losers.”
Having competed at three Olympics and attended four others, Perkins knows better than most that every Games is different.
Whether that be the climate of the host country, the culture, even the layout of the Olympic village, each Games is unique. But the 47-year-old says the rookies may actually have an advantage this time around.
“If this is your first Olympics, you don’t know any better,” he explained.
“You’re not going to be particularly perturbed by it, whereas those athletes who have been before, those differences will be really acute for them.
“There’s probably a higher risk of the differences being a negative influence on the returning athletes.”
Describing himself somewhat modestly as “just a washed-up old swimmer”, Perkins is more than happy to share his extensive experience with today’s stars.
“I’d like to think there’s lessons there for the current team but it’s one of the inexorable truths of time that we’re talking 25 years ago! That’s a really long time ago, especially when you’re talking to young athletes,” he laughed.
“I’m sure our coaches and athletes have got more contemporary examples they can draw from.”
Pressed for a prediction for Tokyo, Perkins hinted that this year’s Games will throw up more surprises than normal.
“The inescapable truth, of course, is that this preparation has been so different from anything that we’ve seen before, so more than usual we won’t know where we stand until competition is underway,” he said.
“That’s always the case for an Olympics, but even more so this time around.”
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