Jasmine Camacho-Quinn won an emotional first athletics gold for Puerto Rico and China took the first title in the track cycling on a day the Games was boosted by news of gymnast Simone Biles' impending return.

After so many days of empty arenas, fans were in attendance at the velodrome, with a 50% capacity of up to 1,800 allowed as the venue is outside Tokyo, where stricter Covid-19 rules apply.

They witnessed a bizarre crash when Australian Alexander Porter's handlebars suddenly snapped off, throwing him forwards at speed on to the floor, with the rider escaping largely unhurt.

And there was a tumble in the athletics, where Dutchwoman Sifan Hassan's bid for an unprecedented treble was nearly derailed when she tripped over in her heat before she recovered to reach the 1500m semi-finals.

But in the women's football, the United States could find no way back after falling behind to Canada as the world champions lost 1-0 in the semi-finals.
Puerto Rico & Greece celebrate athletics firsts

At the Olympic stadium, Puerto Rico won their first ever track and field gold as Camacho-Quinn cruised to victory in the women's 100m hurdles.

The 24-year-old is only the second athlete from the US territory to win an Olympic gold medal, after Monica Puig in the women's tennis singles in 2016.

"I wanted to be a gold medallist and I got it," an emotional Camacho-Quinn said after storming across the line in 12.37 seconds.

World indoor champion Kendra Harrison took silver, to give the US a medal in the women's sprint hurdles for the sixth Olympic Games in a row - the longest medal streak by a single nation in this event in the history of the Games.

Jamaica's Megan Tapper won bronze.

Greek long jumper Miltiadis Tentoglou provided another first - his country's first gold in the event - sealing the title with his final attempt of 8.41m having been outside the medal positions before that. Juan Miguel Echevarria took silver and fellow Cuban Maykel Masso got bronze.

But there was disappointment for Jamaica's 100m bronze medallist Shericka Jackson, who failed to reach the women's 200m semi-finals after finishing fourth in her heat having eased up metres before the line.

There are more athletics medals up for grabs in the evening athletic session, including the women's discus, men's 3,000m steeplechase and women's 5,000m.

That last event features Dutchwoman Hassan seeking the first of three medals she is aiming for at these Games, having also entered the 10,000m as well as the 1,500m.
USA miss out on football final again

The USA arrived in Tokyo favourites for the gold medal in the women's football but they have now failed to qualify for the final for the second successive Games.

They were beaten 1-0 by Canada, with Jessie Fleming scoring the winner from the penalty spot after substitute Deanne Rose was fouled by Tierna Davidson.

Canada will face Australia or Sweden in Friday's gold medal match, while the USA will battle for bronze on Thursday against the loser of Monday's second semi-final.

Biles to return as Carey wins floor in her absence

Pre-Games favourite Simone Biles, who has missed four individual finals while she protects her mental health, was on Monday named in the start list for Tuesday's beam final.

That event is the American's final chance of an individual medal at these Olympics, where her absence has given others an opportunity to shine while she has cheered them on from the stands.

Her team-mate Jade Carey won the floor gold on Monday with her slick and well executed routine impressing the judges in the Ariake Arena.

The 21-year-old's score of 14.366 narrowly beat Italian veteran Vanessa Ferrari into second, who won her first Olympic medal at the fourth time of asking.

There was a tie for the bronze medal between Japan's Mai Murakami and Angelina Melnikova of the Russian Olympic Committee.

China's Liu Yang performed a confident routine to win gold on the rings, with You Hao completing a one-two for China.

Greece's Eleftherios Petrounias, the defending champion from Rio 2016, took the bronze after he landed heavily on his knees.

South Korea's Shin Jea-hwan won the men's vault gold, with Russian Denis Abliazin taking silver and Armenia's Artur Davtyan getting the bronze.
Broken records & snapped handlebars on day one in velodrome

China's women picked up the first gold medal in the Izu Olympic velodrome, edging out Germany in the team sprint final.

The gold medallists, who had broken their own world record in the heats, won with a time of 31.895 seconds.

In the team pursuit heats, Germany also smashed a world record during their Olympic qualifying session, crossing the line in a time of 4:07:307 seconds.

That surpassed the previous record set by Great Britain at Rio 2016 by nearly three seconds.

In the men's team pursuit heats, Australian Alexander Porter had a huge shock when his handlebars snapped off, sending him tumbling to the ground in dramatic fashion.

The 25-year-old skidded across the velodrome's wooden floor, picking up scrapes and cuts, after the apparent equipment malfunction.