This is the first time they have met.
Duan did well for me in the last round. She saved 8 bp in the 3 sets with Sakkari. She won a hard court title earlier this month in China.
Osaka had a decent win over Vandeweghe in the last round. Vandeweghe has a poor record in the US Open but it still needed a strong performance to take the third set. Osaka doesn’t often string 2 good performances together. This should be another tight match and we have some value on Duan