Player to watch: Angelique Kerber

Residence: Kiel, Germany

Age: 23

Rank: 92

5-8, 150

Left handed, two-handed backhand

Next match: Today, Monica Niculescu

Angelique Kerber is in unfamiliar territory. The 23-year-old has never been past the second round of three previous Grand Slam appearances, but she will play another unseeded player, Monica Niculescu, in the fourth round today for a spot in the quarterfinals.

Fellow German Andrea Petkovic foretold good things for Kerber during a tournament in Cincinnati in August. Earlier in the year she called Kerber and asked her to train with her at her academy in Germany. “She came there four weeks and practiced really, really hard,” said Petkovic. “I promise you she’s going to be at least top 30 like in six months, because she worked really and she’s a great player.”

Left shoulder surgery followed by a balky knee in 2009 set her career back. But now a spot in the quarterfinals would go a long way toward breaking into the top 30.