The Northern Irishman is not in New York this week because he is playing at the European Open golf in Switzerland, but he had no reason to be concerned as the top seed eased through to round two.

The first set was reasonably tight, with the Dane gaining the only break in the fourth game, but she upped the tempo in the second to clinch victory in an hour and 20 minutes.

After Llagostera Vives held her serve in the opening game, Wozniacki reeled off six in a row, looking confident on her groundstrokes and proving far too strong for her Spanish opponent.

The 21-year-old made her grand slam breakthrough at Flushing Meadows two years ago, reaching the final before losing to Kim Clijsters, but she has failed to build on that.

Although Wozniacki has enjoyed plenty of success at tournaments outside of the grand slams, she has made only two semi-finals since and has failed to get past the fourth round at the last two slams.