Polish third seed Agnieska Radwanska fought back from 2-5 down in the second set to reach the semi-finals of the BNP Paribas Open with a 6-2 7-6(3) victory over world No 9 Petra Kvitova on Wednesday. Radwanska, who was a runner-up in the event two years ago, raced into a 4-0 lead in the tiebreak before wrapping up victory after a little more than an hour-and-a-half of action at the Indian Wells Tennis Garden in California.