Putintseva 1.60, Duan 2.62
Duan won their only previous meeting. That was in a Chinese ITF hard court event in October 2015. She won in 2 sets.
Overall results are a little better for Duan. On hard courts the stats favour her more strongly. She has won 59% of matches this year. She reached the quarter finals of a WTA Challenger tournament on hard courts last week. In April she got to the semi finals in another Challenger hard court tournament.
Putintseva has won 6 of 17 on hard courts this season (35%) and has won 3 of her last 10. Her game can be quite erratic and the reduced time that hard courts give you to make your shots does not suit her game style well.
Value on Duan as underdog to take at least a set and I think she wins the match. Lay Putintseva around 1.40.