Caroline Wozniacki cruises through with win over Danielle Collins

The Dane, who landed her first major at the Australian Open earlier this year in what was her 43rd Grand Slam attempt, generally prefers faster surfaces, but looked increasingly at ease once she had ironed out some early glitches.

Collins, coming into this tournament on a career-high ranking of 42, fought throughout but was unable to hold off Wozniacki who won on a bizarre point after the umpire ruled a Collins shot had been long while the American, her back turned, was preparing to play on.

Seeded two here, Wozniacki is one of six players who could end the tournament world number one.

“It feels great. A little bit less pressure," Wozniacki said having entered a grand slam for the first time since she won one.

“I kind of feel like I have one grand slam now, so no matter what happens, no-one can take that away from me.

“I’m just out here trying to enjoy every match and every moment of it.”