PARIS — Andrea Petkovic overcame an inconsistent serve and unseeded Kiki Bertens to reach the quarterfinals of the French Open with a 1-6, 6-2, 7-5 victory Monday.

The 28th-seeded German was broken three times in the first set, once in the second and three more times in the third. But she was able to earn seven breaks of her own — all in the final two sets — to advance to the quarterfinals at Roland Garros for the second time in her career.

Bertens, a Dutchwoman ranked No. 148, had been bidding to become the lowest ranked woman to reach the French Open quarterfinals since the field at the clay-court major was expanded to 128 players in 1983.

After splitting the first two sets, the players exchanged breaks quickly and often in the third. Each of the first five games went to the returning player, with Petkovic finally holding to lead 4-2.

Both players were broken once more, but Petkovic was able to hold in the last game with a forehand winner on match point.

“I think she played more aggressively than me when I was a break up,” Petkovic said of the deciding set. “Afterward, I told myself: `Andrea, shut up and play aggressively.’ And it was better.”