Serena books semi-final against Azarenka in Brisbane

BRISBANE: Serena Williams survived a testing examination from fellow American Sloane Stephens at the Brisbane International on Thursday to book a semi-final against world number one Victoria Azarenka.

Williams was pushed all the way by her Fed Cup teammate in the last of the four quarter-finals before winning 6-4, 6-3 in 71 minutes in Pat Rafter Arena.

Earlier Azarenka, of Belarus, swept aside the challenge of Kazakhstan qualifier Ksenia Pervak 6-1, 6-0 in her most impressive display of the tournament.

Williams and Azarenka have met 12 times previously, with Williams winning all but one of those encounters.

Friday's clash will be a tantalising warm-up for this month's Australian Open, where there is a strong possibility the two women will meet in either the semi-finals or final.

Williams, 31, has hardly been pushed this week and was expected to waltz through her clash with 19-year-old Stephens in their first ever meeting.

But Stephens matched the world number three shot for shot, often leaving Williams stranded on the baseline with the power and accuracy of her groundstrokes.

Stephens attacked Williams' serve and had the first opportunity to break but couldn't convert. Williams then took her only break point to win the set.

The second set was almost a carbon copy of the first, this time with Williams breaking at 4-3, before holding to love to claim a highly entertaining match.

Azarenka was in superb form as she crushed Pervak, who had upset former
world number one Caroline Wozniacki in the first round.

The second semi-final will be between two unseeded players after Lesia Tsurenko of Ukraine beat 2012 runner-up Daniela Hantuchova 6-3, 6-4 and Russia's Anastasia Pavlyuchenkova downed fourth seeded German Angelique Kerber 7-6 (7/3), 7-6 (7/3).

The win over Kerber was the powerful Pavlyuchenkova's second defeat of a top 10 player in two days, following her second-round win over Petra Kvitova.

Tsurenko, who lost in qualifying, only made it into the tournament after second seed Maria Sharapova pulled out injured on the eve of the competition. (AFP)