The Bulgarian couldn't convert break points and by the end of his loss to Benoit Paire he had nothing left to give.
To honor their upcoming Beijing tilt, we look back at the great Wozniacki-Kerber Moonball-fest of 2013.
Dominic Thiem's 'tweener handcuffed John Isner and won the Austrian shot of the day honors in Beijing on Tuesday.
"I think nine months season will be good," world No. 8 says in Beijing.
"What I love most about her probably is her head," Andrea Petkovic said of Jelena Jankovic.
No. 11 seed pulls out with hand injury.
The Dutchman Loses his latest encounter in style.