The Netherlands took two more titles to raise its gold tally to eight, all from speed skating, on the penultimate day of the Sochi Olympics which also witnessed a third positive dope test.

The Dutch won the women's team pursuit final against Poland in a new Olympic record time after their men's team beat South Korea for the gold.

The Netherlands has swept 23 of the 36 medals on offer in speed skating and let go only four titles which were split by Poland, South Korea, the Czech Republic and China.

The Olympics was rocked by a third doping case after Ukrainian cross-country skier Marina Lisogor tested positive for the banned substance trimetazidine.

Lisogor, 30, told a disciplinary hearing that she had unwittingly taken the banned substance in a medicine.

The case came a day after news of positive tests for German biathlete Evi Sachenbacher-Stehle and Italian bobsledder William Frullani.

Russia overtook Norway on Friday to top the medal standings with a 11-10-8 record. Norway is second on 11-5-9, followed by Canada (9-10-5), the United States (9-7-11), the Netherlands (8-7-9) and Germany (8-6-5). China is 12th on 3-4-2.

Like the Netherlands, Russia and Austria each picked up two more goals.

Austrian snowboarder Julia Dujmovits came back strongly on the second run to win the women's parallel slalom, while Russian Vic Wild snatched the men's title.

The 26-year-old Dujmovits overcame a huge 0.72-second deficit following the first run, beating Germany's Anke Karstens by just 0.12 seconds after the second.

Wild, the men's giant slalom winner in Sochi, doubled up after winning the men's PSL final against Slovenia's Zan Kosir by 0.11 seconds.

Russia took a shock gold in the men's team biathlon relay which saw Norwegian star Ole Einar Bjoerndalen denied a chance for a historic ninth gold.

Norway's anchorman Emil Hegle Svendsen had a disastrous final standing shoot that put his team out of the contention.

Russia beat Germany by 3.5 seconds as Austria took the bronze.

Bjoerndalen is the most medaled athlete in the winter Olympic history with 13 and tied with Norwegian cross-country skier Bjoern Daehlie on the most golds at eight.

Austria's second gold came from the alpine skiing in which 34-year-old Mario Matt won the men's slalom in 1:41.84, beating teammate and reigning world champion Marcel Hirscher into second by 0.28 seconds.

Norwegian Henrik Kristoffersen, 19, claimed the bronze.

Cross-country skier Marit Bjoergen led Norway's sweep of the medals in the women's 30km mass start, taking her sixth Olympic gold and equalling the record number of medals for a woman at Winter Games.

Meanwhile, the South Korea Skating Union (KSU) has asked for an investigation into the judging that resulted in Vancouver champion Kim Yuna's being awarded silver behind Russia's Adelina Sotnikova in the women's figure skating competition.

Sotnikova, 17, took the gold ahead of 23-year-old Kim to become the first Russian to win gold in the women's free skating on Thursday.

The KSU issued a statement on Friday saying it had met with International Skating Union (ISU) President Ottavio Cinquanta and "officially requested to confirm whether the figure skating ladies single competition was held fairly based on the ISU's regulations and procedures".

More than 1.7 million people, most from South Korea, have signed an online petition calling for a probe into the scoring.