Defending champion Faith Chepng'etich led compatriots Winny Chebet and Edinah Jebitok into sealing their places in the semi-finals of the women's 1500m here at the National Stadium Monday.
Dutch distance runner Sifan Hassan kept also kept alive her hopes of an unprecedented Olympic treble after picking herself up following a fall to win heat 2.
The 28-year-old 1500 and 10,000m world champion crashed to the ground when Kenya's Edinah Jebitok tripped and fell in front of her as the bell went for the final lap
Jebitok, 19, said she was "devastated" after she trailed in 12th in her heat but she was subsequently reinstated and will be in Wednesday's semi-finals.
Chepng'etich comfortablly won the third heat in 4:01.40- the fastest ever heat time at the Games, while Chebet was third in the first heat after timing 4:03.93.
"I am very happy with my performance," said the 27-year-old Faith. "I will not be focusing on Sifan. I will be concentrating on my own race if hopefully we meet in the final."
No fewer than nine women qualified from that heat, including Nozomi Tanaka, who set a Japanese record of 4:02.33. Canadian sisters Gabriela DeBues-Stafford and Lucia Stafford also advanced.
In the 2016 Rio Games, Chepng'etich managed to beat a rich field after bagging victory in 4:08.92, finishing ahead of Ethiopia's Genzebe Dibaba (4:10.27) and USA's Jennifer Simpson.
Chepngetich is the first Kenyan woman to win gold in the 1500m race at a World Championship, achieving the feat at the 2017 Worlds in London, before bagging silver medal in the Doha games in 2019.
Dutch's Sifan Hassan, who is bidding to make history by winning three gold medals, also advanced to the semis after recovering from the fall that affected Jebitok to win heat two.
As the bell sounded for the final lap in the second 1500m heat, world champion Sifan Hassan got tripped and hit the deck. But she got back up and set off in pursuit of the leaders, who at that point were some 40 metres ahead of her.
With less than a lap to play with, Hassan opened up her stride and navigated her way through the field, eventually catching the lead pack as they entered the final straight. She then cruised to the front and won in 4:05.17, having covered the last 300m in 43.7.
She is also set to take part in the 5000m final Monday afternoon.
Additional reporting by AFP