RIO DE JANEIRO -- "You're not working hard enough," Alistair Brownlee yelled at another rider in the 10-man leading pack that had split the field on the triathlon cycle.
He wanted more from them despite the punishing pace at Forte de Copacabana, and it was typical of the aggressive racing style he shares with brother Jonny which made them Olympic champion and silver medallist on Thursday.
The Brownlees were trying to wring every lost drop of strength and stamina from the group as they wheeled towards the crucial third, and final, 10km running leg of the race, all 10 taking it in turn to alternate between slipstreaming and pushing the pace.
The British brothers back themselves to go harder and for longer than anyone else, to obliterate a fatigued field. They are relentless and singled-minded in their pursuit of creating those circumstances in races too; Alistair, the first man to defend an Olympic triathlon title, said he would have preferred the cycle course to have been "a lot harder".
"I know what to look for when people are hurting," he said, and the brothers' competitive nature is such that in a different environment it might sound mean.
There's no sibling sympathy, either. They work together in races and had built a gap between them and the third-placed Frenchman Vincent Luis here on the first lap of the running course. Then, Alistair made his move to attack his brother.
"I started pushing it on," the 28-year-old said. "Jonny said 'relax' and I just thought: if he's telling me to relax he's probably finding this quite hard. So I pushed it on a little bit more."
Ask anyone who has worked with or competed against the Brownlees and they will tell you how hard-working and focused they are. The more healthy suffering they can experience, the better, it seems.
"I have been through hell this year," Alistair said. "Every day has been so hard. I have woken up in pain every day.
"I had ankle surgery not even 12 months ago, at the back end of August last year. I didn't really run pain free until the new year. I am not one to question whether I can do it, but I did.
"I put on quite a lot of weight. But once you start training, training is what I love. Those sessions have been harder than races: a few times a week absolutely killing myself, going to bed not being able to sleep because my legs hurt so much, getting up in the morning and not being able to walk because my ankles were so stiff.
"It's been like that for the last six months with a few bumps and injuries along the way. That's all of it, but the training is what I love doing. Killing myself to finish a session."
It sounds kind of masochistic but that's pretty much par for the course for an endurance athlete. Jonny was on crutches around the same time Alistair had ankle surgery, recovering from a foot stress fracture, and the pair have pushed each other through the pain barrier and back to peak fitness.
The mental strength which they have in spades is at least as important as physical ability and, in that respect, they are lucky to have each other.
It has to relieve the pressure to have your brother out there with you in training and races -- even if, in Jonny's case, he is usually coming off second best when it counts.
There haven't been that many siblings as talented as the Brownlees and they are the first brothers to finish first and second at an Olympics since Italians Piero and Raimondo D'Inzeo in equestrian in 1960; the first British brothers to do so.
"You can always get a first if you look hard enough," said 26-year-old Jonny, towards the end of a Games which has been overflowing with British landmark moments. "But that is a good first and I am very proud of that.
"It's very special to race next to your brother and I'm very fortunate to do that."
The result of their strength and synergy was obvious on Thursday, and their podium positions never really seemed in doubt. Even though neither was the fastest on any of the three legs, they were near the front throughout and the combined effort -- and the tactics which sapped their rivals' energy -- meant they were a long way ahead at the end.
Alistair won in 1 hour, 45 minutes, 1 second, and Jonny's time was only 6 seconds behind, although his older brother had slowed to a walk near the finish line, waiting a little for him and celebrating with a Union Flag and a Yorkshire flag, their English county.
Alistair was determined to drink in the moment, not least because of the contrast to London four years ago when his win felt more like relief because of the pressure to perform in a home Games. "If you can't enjoy having that gap in the Olympic Games, coming down that finishing straight, I don't know what you can enjoy," he said after finishing 42 seconds ahead of third-placed Henri Schoeman, even with the dallying at the line.
The Brownlees collapsed and hugged each other on the other side of the finish here and, as Jonny -- a bronze medallist four years ago -- admitted, he's "not an emotional racer".
The one-two was what they had hoped for in London but, with 2012 silver medallist Javier Gomez absent through injury this time, it was what they had looked forward to here.
How their racing and training partnership, and post-race jubilation, can be reconciled with their individual competitive instincts, however, is hard to fathom.
Jonny insisted he feels no jealousy, although he admitted that the green-eyed monster might haunt him if he gets to the twilight of his career and a golden victory over his brother has still eluded him.
But even the Brownlees don't know really why their sibling rivalry works, no matter how many times they are asked. "We've never had a great answer to it," he said. "It's been going on since we were three years old. Competing at football, table tennis, running round the garden, we've always done it.
"I'm used to getting beat by Alistair but I've gone better than last time in London when I got the bronze. I've actually been training a bit better than him and if it had come down to a sprint, I could win. Maybe in four years, he'll be older, slower and greyer."
The question more is whether the older Brownlee will be fit. In 2012, before his ankle issue, he struggled with an Achilles injury and he has had to work daily on the conditioning for that ever since.
"Triathlon is what I love," Alistair said. "I want to have a go at Ironman at some point and I will be doing some sort of sport. But it has always been about the Olympics for me. I remember watching it in Atlanta when I was eight and the triathlon debut at Sydney when I was 12.
"The Olympics is the big thing and I think it would be hard for me not to be in Tokyo."
Those close to Alistair Brownlee say that once he sets his mind on something, nothing can make him deviate. So, Tokyo it is, then -- and more history as the three-time champion, perhaps. It would take someone seriously special to beat him.