Serena defeats Venus in final

In the rivalry between Serena and Venus Williams, the balance has shifted to the younger sibling of late. And as the two sisters met in the Finals in Doha on Sunday, Serena, looking for her fourth straight win over big sis.

The WTA Tour's season-ending Sony Ericsson Championships - and a nice way to round out the year. Venus against Serena in Doha in Sunday's final.

Venus looked weary - and Serena took full advantage. Serena took the first set comfortably, 6-2.

Venus improved in the second. Although she held serve throughout the set, it was not until 40-0 down in the sixth game that she won her first point against serve since midway through the opening set.

Sheer dogged determination took Venus to a tie-break.

A cross-court winner though, secured a 6-2, 7-6 (4) victory for Serena. It was Serena's fourth straight win over her sister.

She leads their head-to-head record 13-10. And after winning all of her round-robin matches, a cheque for the maximum figure of 1.5 million dollars was hers to keep.

Serena Williams, winner of WTA final, says, "She just missed some key shots and gave me that set and I was just trying to stay pumped. You know, I really did not want to go three sets. That is her favourite thing. She can. I don't know how long I would be able to last if we went three sets. So it was really important for me to try and win that second one."