Having won bronze alongside George Nash in the rowing's men's pair at London 2012, Satch went on to shine as part of Team GB's all-conquering men's eight, winning world titles in 2013, 2014 and 2015 before clinching Olympic gold three years ago in Rio.
But there have been major bumps in the road, with the 30-year-old having gone under the knife in both 2012, to cure a hip problem, and in 2018, to treat atrial fibrillation, a hereditary condition that caused an irregular heartbeat.
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And Satch is still working his way back to full fitness after tearing his pectoral muscle from the bone when testing his limits in the gym with his teammates by attempting a new one-rep max on the bench press.
Satch already has enough glory in the can to go out on a high â€“ but the opportunity to race as a defending Olympic champion in a year's time is just too tempting.
"I'm extremely competitive. I get it from my mum Sally's side," he said, as Team GB athletes marked the one-year anniversary.
"She's a woman that walks down one side of the road and has to walk faster than someone on the other side, who doesn't know they're in a walking race.
"She swam the channel at 13, so that's the athletic, competitive side in me.
After I had heart surgery, George was asking questions like 'why are you doing this? You've achieved it [Olympic gold], so why are you carrying on?'.
"I still knew that I really enjoy the lifestyle. Although it's gruelling, I don't think I'll ever be great sat behind a desk, so I got the operation and then 'sod's law' went on a bench press the following year and got injured.
"I've never been quite content and I always want more, and I think that in this day and age, to do two [Olympic golds] is the ultimate.
"For me, it's always been about going to Tokyo and doing it again.
It's going to be tough, especially because I'm ginger and it's going to be 40 degrees!
Satch isn't lacking in grit - rugby was his first sporting love and he came through the Wasps Academy, where stepdad Martin Unsworth coached and he crossed paths with England international Alec Hepburn.
But after earning a rugby scholarship at Shiplake College, he fell in love with the water.
Team GB will attempt to qualify boats for the next Olympics at this year's World Championships in Austria, in late August, but Satch won't be involved, having opted instead to make up for lost time in training.
But if the men's eight qualifies for Tokyo, Satch is confident of being there to play his part in a title defence.
Scott Durant, Tom Ransley, Andrew Hodge, Matt Gotrel, Pete Reed, Paul Bennett, Matt Langridge, William Satch and Phelan Hill
Image credit: Getty Images
"You've always got to back yourself. I'm reigning Olympic champion and I'm the only one in that eight that has won consistently over those three years, so I kind of know that is my boat," said Satch.
"Having said that, I don't know that is the boat that I will be selected in - you never really know what Jurgen [Grobler, GB Rowing men's coach] is going to do.
I'm confident that the guys will qualify the boat and I'm also confident that I will get back in there. I just need to do the training.
"All of a sudden, I'm one of the most experienced rowers.
"It is definitely a different dynamic within the team because people are looking up to us because we have done it - there's no underdog mentality anymore, which I thrive off.
"But I'm almost quietly confident that winning gold it is achievable."
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