Olympic bronze medallist Eimear Lambe contracted Covid-19 in January and feared she wouldn't make the cut for Tokyo.
Lambe, 23, and her women's team-mates Aifric Keogh, Fiona Murtagh and Emily Hegarty earned the first female medal in rowing when they finished in third place in the women's four final.
The achievement at the Sea Forest Waterway gave Team Ireland their first medal of these Games - and the 32nd medal for Ireland in the history of the Olympics.
But the Dubliner, whose sister Claire raced in the double sculls final in Rio, later revealed that Covid knocked her for six.
And it wasn't looking good for her to be selected for the four until she produced the goods in the final trial.
"I got Covid really in January, so I was taken out for about a month with no training, I was sick in bed, pretty much," said Lambe.
"I had quite a bad cough and headaches and I was quite weak, so it wasn't good for a while.
"So me coming back, I think I wasn't really sure if I was going to make the boat.
"I kind of virtually lost my seat in it, so I was just kind of holding on, trying to work my way back in.
"Obviously there have been a lot sicker, but yeah, I was in bed for about a week and a half, struggling to get up with it.
"I'm surprised how much it took it out of me when I was trying to come back, but lucky I've had a full recovery now and yeah, I'm here."
The quartet clicked into gear in mid-May, earning their passage to the Olympics at that last stage in Lucerne.
"It was definitely devastating because coming into January, then that's when the serious trials start to happen.
"I missed the January trial, I was only back a week for the next trial, so that didn't go well and then there was really only one trial left to decide the boat.
"There was a lot of pressure on it then and I wasn't really sure if I'd be able for it.
"But luckily it worked in my favour. It's such a strong group of girls that obviously any set-back, there's always someone to take your place and luckily I managed to make my way back."
The women's four, along with the rest of the rowing team, are expected to arrive back in Dublin on Sunday.
