Sailor Hannah Mills and rower Mohamed Sbihi have been chosen to carry the flag for Great Britain at Friday's Tokyo Olympics opening ceremony.
Mills, who won gold at Rio 2016 and silver at London 2012, will become the fourth British woman to carry the flag at a summer Games.
It is the first time nations have been allowed to select male and female flag bearers for the Games.
"It's not something I ever dreamed would be a possibility," Mills said.
The 33-year-old told BBC Sport she was "completely overwhelmed" by being chosen to bear the flag.
"I got super emotional when I found out," she said.
"Mark England [Team GB chef de mission] told me in front of the whole sailing team, which was a really cool moment, and then we had to rush out of the door and go sailing.
"I went and had 30 seconds on my own and it all just bubbled up as to what it meant. It is the greatest honour in my career."
Sbihi, also 33, who won gold in the coxless four in Rio and bronze in the men's eight in London, will become the fourth rower to carry the flag at the opening ceremony.
"It is an iconic moment within the Olympic movement - people remember those images," said Sbihi, who missed the opening ceremonies in 2016 and 2012 because of the schedule of the rowing competition.
"It will be really special and will complete my Olympic puzzle. I've won a medal, been to the closing ceremony but now to actually turn up at an opening ceremony and be at the head of the team alongside Hannah, it will be a lifetime memory that I will never forget."
A British Olympic Association panel selected the pair to be flag bearers after each sport put forward athletes to a shortlist.
Olympic and Wimbledon champion Andy Murray carried the flag in Rio five years ago, while cyclist Chris Hoy led Team GB into London's Olympic Stadium in 2012.
Meanwhile, the show director of the opening ceremony, Kentaro Kobayashi, has been dismissed after footage from the 1990s recently emerged in which he seems to be making jokes about the Holocaust.
After his removal, organisers are now reassessing how to hold Friday's event.
It comes days after a composer quit the team creating the ceremony after it emerged he had bullied classmates with disabilities at school.
Organisers have also confirmed that two more athletes in the village are among 12 new cases positive cases of Covid-19, bringing the total of cases related to Games personnel to 91.
The opening ceremony begins at midday BST on Friday and will be live on BBC One, BBC Red Button and online.
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