Former World No. 1 Caroline Wozniacki continued her undefeated run at New Haven with a straight-set victory over Russian Ekaterina Makarova Monday at the $637,000 New Haven Open at Yale.

The third-seeded Dane, who defeated Czech Petra Cetkovska in last year's finale to claim her fourth straight title at this event, needed just 81 minutes to top Makarova 6-3, 6-3 in a straight-set triumph.

Wozniacki is now 18-0 lifetime at the New Haven Open at Yale.

Meanwhile, fourth-seeded French Open runner-up Sara Errani of Italy took care of American wild card Bethanie Mattek-Sands 6-4, 7-5 and seventh-seeded Russian Maria Kirilenko drilled struggling Israeli Shahar Peer 6-2, 6-2 at this final U.S. Open tune-up on the hardcourts at the Connecticut Tennis Center.

In other opening-round action on Day 2, Nicole Gibbs topped fellow American qualifier Alexa Glatch 6-4, 1-6, 6-4; German Mona Barthel grounded Slovak Daniela Hantuchova 6-3, 7-5; Swede Sofia Arvidsson dropped American lucky- loser Melanie Oudin 6-4, 6-1; Olga Govortsova of Belarus ousted Russian Vera Dushevina 6-7 (5-7), 6-4, 6-2 and German Andrea Petkovic downed Timea Babos of Hungary 6-3, 5-7, 7-5.

Slovakia's Dominika Cibulkova, who is the sixth seed at this tournament, also advanced with a 7-5, 6-3 victory over Spain's Anabel Medina Garrigues.

This week's top-two seeds are Wimbledon runner-up Agnieszka Radwanska and former Wimbledon champion Petra Kvitova, who will meet the 19-year-old Gibbs in the second round.

The 2012 New Haven champion will collect $107,000.