China claimed three gold medals on the first day of the Tokyo Olympics on Saturday and cyclist Richard Carapaz became just the second competitor in Ecuador's history to top the podium, with victory in the road race.

As the troubled build-up to the pandemic-postponed Games gave way to the first full day of competition, China secured victories in shooting and weightlifting.

Yang Qian sparked the mini gold rush in the 10-metre air rifle competition, pipping Russia's Anastasiia Galashina with a dramatic last-shot victory to take the very first title of the Games.

Serbia's Novak Djokovic is bidding for a "Golden Grand Slam"
Serbia's Novak Djokovic is bidding for a "Golden Grand Slam" AFP / Jeff PACHOUD

Galashina had looked poised to win heading into the last shot, but stumbled with 8.9 on her final effort to allow Yang to grab gold.

"It's the 100th birthday of the Chinese Communist Party," she said. "I'm so happy that this golden medal is a gift to my country. I'm so proud."

There was more joy for China, with Hou Zhihui taking gold in the women's 49kg weightlifting event with an Olympic record total of 210 kilograms.

Fireworks light up the sky over the Olympic Stadium during the opening ceremony of the Tokyo 2020 Games
Fireworks light up the sky over the Olympic Stadium during the opening ceremony of the Tokyo 2020 Games AFP / Kazuhiro NOGI

Fencer Sun Yiwen added a third Chinese gold of the day with victory in the women's epee.

In cycling's gruelling road race, 2019 Giro d'Italia winner Carapaz outfoxed a heavyweight field led by Slovenia's Tour de France champion Tadej Pogacar.

It was only Ecuador's second gold at the Olympics after Jefferson Perez's victory in the 50km race walk at the 1996 Atlanta Games.

Tour de France winner Tadej Pogacar is gunning for Olympic gold
Tour de France winner Tadej Pogacar is gunning for Olympic gold AFP / Anne-Christine POUJOULAT

Japan celebrated the first goal medal of its Games when judoka Naohisa Takato won the men's 60kg final at the iconic Nippon Budokan, beating Taiwan's Yang Yung-wei.

But the host nation suffered disappointment when gymnastics great Kohei Uchimura's campaign came to an early end.

The two-time all-around Olympic champion slipped up in qualifying for the horizontal bar competition, having battled a shoulder injury to be fit for the Games.

China's Yang Qian celebrates after winning the women's 10m air rifle competition at the 2020 Olympics
China's Yang Qian celebrates after winning the women's 10m air rifle competition at the 2020 Olympics AFP / Tauseef MUSTAFA

"In the last three Olympic Games I've been able to match the level of performance I'd reached in training -- but not this time," a dejected Uchimura said.

In another Japanese setback, world champion Daiya Seto failed to reach the final of the men's 400 metre medley in the pool, although he has two more events.

Naomi Osaka lit the Olympic cauldron as the Games officially opened
Naomi Osaka lit the Olympic cauldron as the Games officially opened POOL / HANNAH MCKAY

With spectators barred from almost all Olympic venues due to Covid-19 restrictions, the road race was a rare chance for domestic fans to glimpse the action.

Tens of thousands lined the route of the brutal 234km (145-mile) course to watch as Carapaz prevailed in a thrilling tactical battle.

"It's an incredible moment for me," Carapaz said. "You always have to believe. I have worked so hard to be here and it's a huge moment for me."

The spectre of Covid-19 continued to stalk the Games when German cyclist Simon Geschke was forced out of the road race while Dutch rower Finn Florijn has also tested positive.

Seventeen new Games-related cases were announced, taking the total number to 123, of which 12 are athletes.

Organisers were also nervously tracking the progress of a tropical storm heading towards Tokyo, with forecasters saying it could arrive on Tuesday.

As a "protective measure", organisers have brought forward to this weekend rowing events scheduled for Monday.

Elsewhere on Saturday, world number one Novak Djokovic stayed on course for a Golden Grand Slam with a comfortable 6-2, 6-2 defeat of Bolivia's Hugo Dellien in the opening round of the men's singles tournament.

Djokovic, who has already won the Australian Open, French Open and Wimbledon titles this year, is bidding to win all four majors in a calendar year as well as Olympic gold, emulating the feat of German great Steffi Graf in 1988.

Naomi Osaka, fresh from her starring role lighting the Olympic cauldron in Friday's opening ceremony, starts her bid to win gold for Japan on Sunday.

The swimming events began with Britain's Adam Peaty blasting through his heat to kickstart the defence of his 100m breaststroke title.

Peaty, 26, who has lowered the world record five times and is arguably the greatest ever over the distance, hit the wall in an eye-catching 57.56 sec.

American Michael Andrew, who caused a stir by refusing to be vaccinated against Covid-19 before heading to Tokyo, was third fastest.

Meanwhile, Hungary's evergreen fencer Aron Szilagyi made Olympic fencing history as he took the sabre title for a third time in a row.

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