Updated

Defending champion Agnieszka Radwanska of Poland and Russian Nadia Petrova each earned straight-set victories in their semifinal matchups at the Pan Pacific Open on Friday.

The third-seeded Radwanska, who defeated Vera Zvonareva in last year's final, made quick work of Angelique Kerber, whipping the fifth-seeded German 6-1, 6-1 in just 59 minutes.

"We've played a couple of times before and it has always been tough, and even though today was 6-1, 6-1 it was tough as well, and I had to run a lot," said Radwanska. "She's a very smart player and mixes up a lot of shots, so I had to stay focused from beginning to end. I'm very happy I could play my best today."

The Wimbledon runner-up Radwanska blasted 20 winners and committed just four unforced errors in the rout.

"My game plan was to be aggressive, but Agnieszka was playing very well and bringing every ball back like a ball machine," said Kerber, who was also beaten by Radwanska in the second round of this event last year. "I fought until the last point, but unfortunately it didn't work out for me today. She played too well."

The 23-year-old Radwanska will try to capture her 11th career WTA title and fourth this year when she faces Petrova, who smashed nine aces and saved all three break points against her serve en route to a 6-4, 6-2 upset against eighth-seeded Australian Samantha Stosur.

The 17th seed improved to 6-3 lifetime against Stosur, who knocked off second-seeded Maria Sharapova on Thursday.

Petrova will be vying for her 12th career WTA title and second in 2012, having won the Wimbledon tune-up in the Netherlands back in June. The 30-year-old tour veteran is 11-11 in WTA finals.

Radwanska, who is 10-3 all-time in finals, owns a 3-1 lifetime mark against Petrova. All four matches were played in 2008, including a 6-3, 6-0 Petrova rout in the quarterfinals of this event. Radwanska won the only previous final between the two, a 6-4, 6-7 (11-13), 6-4 thriller at the Wimbledon tune-up in Eastbourne.

Saturday's winner will earn a first prize of $385,000.