Caroline Wozniacki edged past Lucie Hradecka in three sets to reach the second round of the China Open in Beijing.
Wozniacki scraped through 3-6, 6-0, 7-5 against the big serving Czech, saving two break points at 4-4 in the third set and the defending champion admitted afterwards she was relieved to progress.
"She's a player who doesn't give you any rhythm. She's serving 200kph serves so when it's on it's difficult," Wozniacki said. "In the second set her first serve percentage dropped, which made it easier for me to start the rallies. It wasn't a pretty match today but I'm through, and that's what's most important."
Wozniacki won the Beijing title last year and she really needs to go deep to keep her chances of holding on to the world number one spot.
Her chances have been aided by early exits for Sabine Lisicki and Francesca Schiavone who both crashed out in the second round.
Wozniacki will now play the big serving Aussie Jarmila Gajdosova in round two. Gajdosova cruised past Spain's Anabel Medina Garrigues 6-3, 6-0 in the opening round.
