The 35-year-old missed gold by just five metres – or one second on the clock – after a gruelling one-on-one contest with Hug, of Switzerland.

The pair split from the pack early and went head-to-head for the rest of the five-lap event in sapping conditions at Rio's famous Copacabana beach. It was only within sight of the finish line that Hug, 30, broke the Australian. 

"Marathons are just brutal, you know. You go out there and you control everything physically and you throw everything you've got at it," an emotional Fearnley said.

"With 200 (metres) to go … I had kind of stopped. Marcel was a very deserving winner."

Fearnley's silver means he's won marathon medals at four straight Paralympics. At the first – in Athens 2004 when he claimed gold – he had encouraging words for a then 18-year-old Hug, who'd picked up two bronze medals in wheelchair racing.

"I actually swapped my shirt with him that day because I actually said to him 'there's impressive things to come'," Fearnley said. 

"I probably should have taken those nice words back!

"I wouldn't. I'm proud of him."

Hug, 30, has two golds and two silvers from these Games. The Swiss was happy to work in unison with Fearnley and close out the rest of the field.

"We heard that the gap with the second group was growing more and more, and so we just worked together to come to the sprint together and then the faster would win," he said.

Fearnley explains further: "When we got a metre we decided to put the head down and, without saying a word with Marcel, we put the head down and made it five metres. One sneaky look back and all of a sudden it was a kilometre."

While the legendary Australian athlete leaves Rio without the third marathon gold he so desperately sought, unable to top the podium since Beijing eight years ago, there are no regrets. Thirteen medals from five Paralympics - including two marathon golds, one bronze and now a silver - can attest to that.

"It's been an amazing run – these last 16 years," he says.

"I think I ran about 32nd in my Paralympic marathon back in Sydney. And I'm grateful for that start. 

"That start is the thing that has given me the next 16 years to build on. I'm as proud of that day as I'm today."

And today was also about family. On the course were family and friends, including his wife Sheridan and two-year-old son Harry. 

"Mate, it's a day that he may never remember but it's a day I won't forget," Fearnley said.

Even without crawling the Kokoda Trail or inspiring countless young athletes with impairments, Fearnley's impact has been profound. Australia's athletics team leader in Rio, Adam Faichney, said he deserved the role as Australia's co-captain.

"This is a fantastic way to bow out," Faichney said.

"They [Fearnley and Hug] took it out from the start and made sure that they the rest of them were battling out for third. That's typical of (Kurt), he takes the bull by the horns and has a crack."

You haven't seen the last of this wheelchair racer. He's set for an appearance at the 2018 Commonwealth Games and the international circuit of London, Boston and New York remains.

What is likely to be behind him, however, are the fierce conditions that often present themselves at Paralympics competition.

"Most of the marathons around the world are run in four degrees," Fearnley says.

"I always back myself when it's an uncomfortable marathon, when it's something that's going make people hurt, then I back myself to go pretty handy at it."

So handy, in fact, that first place was barely one second away.