Puspure, the world champion in both 2018 and 2019, is one of Ireland’s biggest medal hopes for the Games.
The 39-year-old, born in Latvia but a long-time resident of Ireland, won her heat at the Sea Forest Waterway with more than eight seconds to spare to cruise through to the quarter-finals.
Puspure said: “It was OK, first race done. I’m taking it one race at a time, not thinking too far ahead, calm and collected.”
She is well aware that expectations in Ireland, where her husband and two children are among those watching, are sky high.
“I read all the messages, I don’t reply to them but I soak in all the positive energy and positive vibes from home and I’ll get back to all the people who wished me well after the Games,” she said.
“We had a really good training camp in Italy so we’ll just have to wait and see. You just think about the next race that you have to do and not the race that you may be doing in a week’s time.”
Thornley, the first British female single sculler to gain Olympic selection for 20 years, also crossed the line first in her heat, nearly three seconds ahead of Switzerland’s Jeannine Gmelin.
“Coming to the Olympics in the singles has been a dream of mine for a long time so it’s great to finally be out here racing in the boat I love,” said the 33-year-old, who won silver alongside Katherine Grainger in the double five years ago.
The heat will be a factor at all outdoor sports, and Thornley undertook her press duties while donning an ice vest and ice packs.
She said: “It’s obviously hot but I felt cool on the start line, which was good. You cross the line and it’s pretty warm but we all knew it was going to be like this.
“The conditions have been pretty similar to what it’s been in training, so definitely good to get the first race done, and it went pretty much how I wanted it too.”
British duo Graeme Thomas and John Collins made it through to the semi-finals in the double sculls, finishing second in their heat behind the Dutch, but both the men’s and women’s quadruple sculls will have to go through the repechage.
Thomas missed the Rio Olympics through illness, and he said: “Our physio Liz came over and gave me a pat on the back, said congratulations, there were definitely tears behind the sunglasses.
“I am not going to lie, there has definitely been a bit of anxiety in the few weeks leading off and especially with the added Covid factor on top. With it being a virus in 2016, it does exacerbate the fear of something going wrong again.
“It is a big relief to get that out of the way and now I can call myself an Olympian and the job is now winning a medal for GB with John.”
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