MELBOURNE, Australia—Caroline Wozniacki defeated Donna Vekic of Croatia 6-1, 6-4 on Thursday to advance to the third round of the Australian Open.

Wozniacki played her 72-minute match during the hottest part of the afternoon when the temperature at Melbourne Park peaked at 106 degrees.

The 10th-ranked Wozniacki was the No. 1 player in the world here last year, but faced criticism that she had never won a Grand Slam.

She failed to change that in 2012, losing in the quarterfinals at Melbourne Park, the third round at the French Open and the first rounds at both Wimbledon and the U.S. Open.