Swimmer Tom Dean sensationally clinched Britain's fourth gold of the Tokyo Games on day four of the Olympics, six months after he contracted Covid for a second time.
The 21-year-old, who struggled to walk up stairs after contracting the virus, edged out compatriot Duncan Scott by 0.04 seconds in the 200m freestyle.
Elsewhere, Georgia Taylor-Brown fought back from a puncture on the last lap of the bike leg to take triathlon silver.
The Briton was 22 seconds off the four-strong leading pack going into the run.
But she reeled in all her rivals except for Bermuda's Flora Duffy to claim an emotional second-place finish.
It is Britain's second triathlon silver after Alex Yee's success on Monday.
Coming up on Tuesday
09:00 BST: Britain's Carl Hester, Charlotte Dujardin and Charlotte Fry aim to upset Germany in the dressage team final
11:45 BST: Great Britain's gymnastics team compete in the women's team final in which the United States and Russia are expected to contest gold
13:30 BST: Bianca Walkden compete in the taekwondo +67kg quarter-finals, attempting to make up for house-mate Jade Jones' early exit.
'Olympic gold seemed a million miles'
Dean's preparations for Tokyo were badly disrupted by Covid, with the 21-year-old losing more than six weeks of training after contracting the illness twice.
"When I was sitting in my flat in isolation, an Olympic gold seemed a million miles off," he said.
"I had Covid in September and the New Year. The first time wasn't too bad. The second time I did the full isolation period, I wasn't able to train and it was a slow-build back into training."
Dean's team-mate Scott was favourite going into the final after qualifying fastest, but was beaten to the touch in a tight finish.
The result is Britain's first swimming one-two in 113 years with both men cheered on by Adam Peaty, who successfully defended his 100m breaststroke title on Monday.
Taylor-Brown battles wind, rain and wheel rims to take silver
Taylor-Brown, 27, revealed after the finish that she had overcome a stress fracture to her leg to make the startline, passing a late fitness test a week before departing for Tokyo.
"My training had gone so well before then though, so that was a bit of a shock, but I knew I had all of that training in the bag," she said.
"I wanted to keep it private. You don't want to show your competitors your weaknesses."Tokyo day-by-day guideTV schedule, radio and online coverageTokyo 2020 medal table
Her preparations for a race in hot, humid conditions were thrown by Tropical Storm Nepartak which brought high winds and heavy rain to the startline.
Then, on the bike leg, she was up with the leaders before a flat rear tyre saw her slip back on the final kilometre of the 40km bike leg.
Afterwards, she said she "panicked" when the incident happened.
"I didn't know what to do, so I just rode out on the flat. It was panic mode but it paid off," she told BBC Sport.
Gold medallist Duffy's success marked a piece of history as Bermuda became the least populous nation ever to win an Olympic gold.