Momota suffered multiple lacerations to his face and a fractured nose.
Badminton world number one Kento Momota was injured in a pre-dawn vehicle collision in Malaysia on Monday, just hours after he secured his first victory of the season at the Malaysia Masters.
The Japanese shuttler and three others were thought to have been en route to Kuala Lumpur international airport when the hired van they were in rammed into the rear of a 30-tonne truck, according to statements from the police and local fire department.
The driver of the van was killed in the incident, and his body had to be cut free from the wreckage.
Police and Malaysia's badminton association (BAM) said that in addition to Momota, the three others involved in the incident were his physiotherapist, his assistant coach and a Badminton World Federation official.
The association said in a statement that Momota suffered multiple lacerations to his face and a fractured nose.
Malaysia's Health Minister Dzulkefly Ahmad said the four were in stable condition and would be discharged once hospital officials were satisfied they were fit to be released.
"Based on investigations and CT scans, there are no major injuries... they are now stable and will be given continued treatment and remain under observation for now," Dzulkefly said briefly outside Putrajaya Hospital where the four are being treated.
Japan's ambassador to Malaysia, Hiroshi Oka, who was with Dzulkefly on the visit, was grateful for the "care and support" given to those involved in the crash.
On Sunday, Momota defeated former world champion Viktor Axelsen to win the Malaysia Masters, the first tournament of the BWF 2020 World Tour season.