Venus hit a forehand volley wide on breakpoint at 5 all with Serena serving before netting a backhand as Serena reached 6-5.
Even though trailing in the match, Venus, seeded 7th controlled many of the points, hitting either a winner or error. A winner and an error struck from Venus' forehand combined with an aggressive Serena backhand return set up a Serena set point.
Serena, seeded 3rd, would break serve as Venus would commit a backhand error on setpoint number two.
In the second set, Venus broke serve then held for a 2-0 lead before Serena held serve at love to win her lone game of the final two sets to reach 2-1 in set two.
Venus' pace and power put Serena in an unfamiliar position as Serena found herself on the run for much of the remainder of the match hitting one-handed backhand slices and adding more topspin in the place of her normal flat powered groundstrokes.
A Venus crosscourt backhand passing shot winner sealed set two as Serena had only managed to win one game the entire set.
In the final set, Venus steamrolled as she eliminated the earlier errors from her game as Serena would commit more errors. A Serena backhand wide ended the 1 hour 48 minutes match.
With the win, Venus advanced to the semifinals at Doha and tied her head to head with her sister 9-9. But due to the rare round robin tournament format this week, Serena could also reach the semifinals with a win in her final round robin match Friday.
For the match, Venus would strike 30 winners to 11 unforced errors while breaking Serena's serve 8 times. Venus had won the last 10 games of the match.
“I'm pretty excited,” Venus said. “I tried to cut down on those errors. I want to be fitter and work a little harder in the off season.”