Top Indian shuttler P V Sindhu had to dig deep into her reservoir of experience to beat unseeded Mia Blichfeldt of Denmark and claim a quarterfinal berth in the women's singles event of the Indonesia Open here Thursday.

Sindhu, seeded fifth, slugged it out for one hour and two minutes to get the better of Blichfeldt 21-14 17-21 21-11 in a second-round encounter.