Tennis:Elena Dementieva defeated defending champion Venus Williams at the Sony Ericsson Championship in Doha.
The Russian came back from a set down to defeat the seven-time Grand Slam winner 3-6 7-6 (8-6) 6-2 to take the early lead in the Maroon Group.
Venus' sister Serena Williams now faces Svetlana Kuznetsova.
Victoria Azarenka made short work of Jelena Jankovic on her debut in the tournament.
The Belorussian raced to a 6-2 6-3 win over her Serbian opponent in one hour 22 minutes in the opening match of the tournament, which features the top eight players in the world.
It was Azarenka's second win over Jankovic in their fifth career meeting, and her success on her opponents' serve proved key.
Azarenka broke twice in the first set and three times in the second to pave the way for victory.
The 20-year-old won 50% of points of Jankovic's first serve and 60% on her second, carving out nine break opportunities.
She faced just two break points of her own, losing one.
Azarenka and Jankovic are in the White Group along with Russian Dinara Safina, the world number one, and Denmark's Caroline Wozniacki.
The top two players from each group advance to the semi-finals.