World number one
Naomi Osaka and 23-time Grand Slam champion
Serena Williams were both knocked out in the third round of the
French Open on Saturday, becoming the latest seeded players to crash out of the women's draw.
Osaka's hopes of winning a third successive Grand Slam ended when the Japanese top seed was roundly defeated by the unheralded Katerina Siniakova of the Czech Republic.
Later on, Williams slumped to her earliest exit in a Grand Slam tournament since 2014, also losing in straight sets to fellow American Sofia Kenin.
Their defeats mean that only three of the top 10 seeds in the women's singles are left in the tournament.
Osaka, the reigning US and Australian Open champion, lost 6-4, 6-2 to the 42nd-ranked Czech.
The world number one was undone by a shocking 38 unforced errors as she finally ran out of luck at Roland Garros having had to come back from a set down in her first two matches.
"It's amazing, I can't believe it, I am so happy now," said Siniakova, who was the women's doubles champion in Paris in 2018 alongside Barbora Krejcikova.
Despite being seeded top for the first time at a Slam, the 21-year-old Osaka had never looked convincing in Paris.
She was two points away from defeat in the first round against Anna Karolina Schmiedlova and came back from a set and break down to see off Victoria Azarenka in round two.
Break points squanderedOsaka dropped the first set for the third successive match at the tournament, squandering seven break points in all.
Siniakova made her pay, breaking for 5-4 and taking the opener when Osaka sent back her 16th unforced error of the set.
The Czech, who is the world's number one doubles player, kept up the pressure on the misfiring top seed, breaking for a 3-2 lead in the second set.
Siniakova backed it up with another break for 5-2 off Osaka's third double fault of the match.
Victory was hers on Court Suzanne Lenglen when Osaka unleashed another misguided forehand.
The Czech goes on to face Madison Keys, who knocked out Russian qualifier Anna Blinkova, in what will be her first appearance in the last 16 of the majors.
Williams' Slam history bid haltedOsaka was trying to become the first woman to win three consecutive major trophies since Williams grabbed four in a row in 2014-15, a run that was preceded by a second-round loss at Roland Garros and a third-round loss at Wimbledon.
Since those early defeats, Williams had won six of the 14 majors she entered to surpass Steffi Graf's professional-era record of 22 Grand Slam singles championships. With 23, she is still one short of the record set by Margaret Court, who also played in the amateur era.
Williams, now aged 37, came to Paris having played only four matches since a quarter-final exit at the Australian Open. She withdrew from two tournaments because of an injured left knee and another because of illness.
She struggled through her opening match at Roland Garros, and was again on the back-foot against the 35th-ranked Kenin, who has never made it this far in a Grand Slam tournament.
Kenin played well, never showing a trace of nerves, and conceding just 17 unforced errors to her opponent’s 34.
Remarkably, Kenin broke Williams four times, while only ceding one of her own service games.