Adam Peaty began the defence of his Olympic 100m breaststroke title in impressive style as Team GB beat hosts Japan in the women's football on day one of the Tokyo 2020 Games.
In Sapporo, Ellen White scored GB's only goal of the game as Hege Riise's side continued their winning start to the Olympics.
Earlier, Helen Glover's ambition to retain her women's pairs rowing title got off to a shaky start alongside Polly Swann.
In what was Glover's first defeat in more than a decade, she and Swann finished third in their heat, some way off the pace but enough to ensure their berth in Tuesday's semi-finals.
Team GB's Andy Murray and Joe Salisbury got off to a promising start in the men's doubles, beating French second seeds Pierre-Hugues Herbert and Nicolas Mahut 6-3 6-2.
In gymnastics, defending champion Max Whitlock eased through to the pommel horse final with a score of 14.900 points in qualification.
And if all that isn't enough, here's some of what else happened on Saturday.GB men's hockey won their first game against South Africa 3-1.GB's Adam Yates finished ninth in a gruelling men's cycling road race, won by Ecuador's Richard Carapaz. Geraint Thomas did not finish after crashing.British badminton players Marcus Ellis and Lauren Smith won their opening mixed doubles match, beating France's Thom Gicquel and Delphine Delrue 21-18 21-17.In the pool, James Wilby, Aimee Wilmott and Max Litchfield were among the swimmers progressing in their events.Charlotte Fry cruised into the individual dressage final, topping her qualifying group with Everdale with a personal best score of 77.096%.British boxer Karriss Artingstall beat Botswana's Keamogetse Sadie Kenosi, the world number four, in her opening bout.
Peaty eases into semi-finals
World record holder Peaty is GB's strongest hope for a medal in Tokyo and he got his campaign off to the perfect start as he topped the timesheets in the 100m breaststroke.
The 26-year-old, who won the event in Rio five years ago and is unbeaten over the distance since 2014, is aiming to become the first British swimmer to retain an Olympic title.
Arno Kamminga of the Netherlands, one of Peaty's biggest rivals for gold, was only 0.24 seconds slower in second overall, while fellow Briton Wilby qualified in sixth place.
Peaty will go again in the semi-finals on Sunday (03:33 BST) with his world record of 56.88secs likely to be threatened.
"[It was] really weird with no crowd, really weird," Peaty said afterwards.
"It doesn't feel like an Olympics. It's not the same, of course it's not, but obviously when you go back to the [athletes'] village, that's when it does.
"Heats are heats. I always have cobwebs - it's pretty much the exact same time I did in Rio - and I always build on that. We will just see where we go from here."
GB's footballers guarantee knockouts place
Great Britain guaranteed their progress to the knockout stages of the women's football with victory over London 2012 silver medallists Japan.
White scored the winner, her third goal of the tournament, nodding in a cross from full-back Lucy Bronze in the 74th minute.
They now top Group E with one game remaining, against Canada on Tuesday (12:00 BST kick-off).
Team GB head coach Hege Riise said: "We are all happy with two wins now. It puts us in a good position, able to rest players and recover well - we are very happy.
"We put Sophie Ingle in more as a defensive player against Japan, I think that worked well.
"Of course attacking-wise we lacked a little, but we knew that could happen. I feel like the connection has got better and better each game and that's what we need to get used to.
"In the second half we changed the formation a little. We came out well and controlled the game much better."
'Not our perfect row' for Glover & Swann
Glover has become the first British mother to row at an Olympics but her impressive comeback has not gone entirely smoothly in Japan.
Her defeat with Swann in the heat - won by Australia - was Glover's first since 2011, a run spanning 51 races and including Olympic golds in 2012 and 2016 alongside Heather Stanning.
"It wasn't our perfect row but I guess there's value in learning in the early rounds," she said. "We're open to what's going to come next."
Elsewhere for GB's rowers, the men's four - the British boat bidding for its sixth consecutive gold in the event - won their heat to progress to the final. The quartet of Ollie Cook, Matt Rossiter, Rory Gibbs and Sholto Carnegie are all making their Olympic debuts and have got big shoes to fill.
Emily Craig and Imogen Grant are into the semi-finals of the lightweight double sculls, but the women's four and men's eight must go again in the repechages if they are to reach the finals after finishing fourth and third in their heats respectively.
Murray and Salisbury win but Watson out
Murray and Salisbury's doubles partnership is a new one but one that seems to have gelled nicely, as they beat the French Open champions.
Murray is the defending two-time Olympic champion in the men's singles and won silver in the mixed doubles at London 2012 with Laura Robson, while Salisbury is making his Olympic debut.
They will play Germany's Tim Puetz and Kevin Krawietz next for a place in the quarter-finals.
But it was an early exit for Heather Watson, who lost 7-6 (7-5) 6-3 to Germany's Anna-Lena Friedsam in the first round of the women's singles.
Jamie Murray and Neal Skupski later beat Argentina's Andres Molteni and Horacio Zeballos 6-7 (3-7) 6-4 (13-11).
A warning for athletes
Olympics Games executive director Christophe Dubi has warned athletes they will be punished if they ignore anti-Covid measures.
It follows Friday's opening ceremony in which most of the Kyrgyztan and Tajikistan team members along with Pakistan's two flag bearers did not wear masks, which are required at all times, except for when training, competing, eating or sleeping.
One more athlete has tested positive for Covid-19, the 12th competitor to return a positive test in Tokyo and the 123rd case in total.
Dutch rower Finn Florijn is the first athlete to test positive for Covid-19 after competing in Tokyo.
He finished fourth in his heat of the men's single sculls race on Friday, and was due to race in the repechages on Saturday, but was withdrawn from the Games.
There are also concerns about the heat in Tokyo, after a Russian archer fainted in the high temperatures during qualifying on Friday, while the rowing schedule was changed as a result.
Cyclists in the men's road race visibly struggled with the heat, spraying water down themselves and putting ice packs in their jerseys, and tennis player Anastasia Pavlyuchenkova had to take a medical timeout after feeling dizzy.