Updated

Top-seeded Agnieszka Radwanska was a straight-set winner Thursday and advanced to the semifinals at the ASB Classic tennis event.

The Wimbledon runner-up Radwanska, of Poland, rolled past Russia's Elena Vesnina 6-3, 6-3 on the hardcourts at ASB Tennis Centre, despite a lengthy rain delay early in the second set. Vesnina was the runner-up here in 2009.

Jamie Hampton awaits Radwanska in the semifinals after the 22-year-old American earned her first-ever trip into a WTA semi with a 6-1, 6-7 (5-7), 6-2 victory against Kiki Bertens of the Netherlands.

Yanina Wickmayer, the third seed out of Belgium, advanced with a 6-3, 6-4 victory over compatriot Kirsten Flipkens.

The 2010 champion and 2011 Auckland runner-up Wickmayer will face eighth- seeded German Mona Barthel in the final four. Barthel cruised past Sweden's Johanna Larsson 6-2, 6-1 to advance.

This event serves as a tune-up for the Australian Open, which starts January 14.