Defending champion Victoria Azarenka was knocked out in the first round of the China Open on Monday, losing 6-4, 2-6, 6-4 to Andrea Petkovic.
The second-ranked Azarenka double-faulted 15 times and was broken five times by Petkovic, who reached the final here in 2011.
"I'm very happy with my performance," Petkovic said. "I was happy with my movement and my serve for the most part, and I managed to get a lot of balls back very deep and very strong. Parts of the match were a really, really good level - some parts I lost a bit of energy, but overall I'm very happy."
It was the second tournament in row in which Azarenka lost her first match, having been beaten by Venus Williams in Tokyo last week.
"It was an awful match and a very bad performance from me, so there's not much to say about it," Azarenka said. "It happens once, twice a year to every player, and it happened to me today."
Also Monday, eighth-seeded Jelena Jankovic ralli...