Indian qualifier Sania Mirza edged past Vania King in a three set battle to book a pre-quarterfinal berth in the WTA Family Circle Cup in Charleston, USA.
Showing nerves of steel, Sania erased a one set deficit to score a 6-7(6) 6-4 6-2 win over in form local player, Vania king, in the second round of the USD 721,000 hard court event.
King had ousted 16th seed Russian Vera Dushevina in her opening round.
Sania will fight it out with either fourth seed Marion Bartoli of France or German wild card Sabine Lisicki for a spot in the last eight.
Lisicki and world number 10 Bartoli will clash in their second round on Wednesday.