A day after securing the No 1 ranking, Serena Williams downed Maria Sharapova for a 10th straight time 6-3, 6-2 to reach the Qatar Open final today.
Williams will face Victoria Azarenka, whom she will replace at the top in Monday's new rankings update. Azarenka beat Agnieszka Radwanska 6-3, 6-3 in the other semi-final, earning her 13th straight victory in 2013.
While Azarenka has been on a roll, she doesn't have a good record against Williams. The American is up 11-1 in their head-to-heads, including winning their last nine matches.
Williams, who had been inconsistent for much of the week and struggled with her first serve, looked her old self at Sharapova's expense. The third-ranked Russian had no answer for Williams' first or even second serve, which resulted in six aces and 78 per cent of first-service points won.
Both players served well early but it was a double fault from Sharapova that gave Williams the only break of the first set at 4-2. She consolidated the break with a love service game and closed out the set with two aces.
Sharapova came out stronger in the second and had a chance to go up 2-0. But Williams saved the break point and broke to go up 2-1. Williams broke again to make it 5-2. Serving for the match, she tightened up but saved a break point and prevailed when Sharapova hit a crosscourt forehand wide.
Sharapova blamed her failure to return well for the loss.
"I mean, in the first few games it was close. I thought I had a few opportunities in her service games, love 15, love 30, 15-30, and I didn't use that to my advantage," Sharapova said.
"Against someone like Serena who is a great server in those situations, if you don't use them, don't put pressure on your opponent, you know, they gain a little bit of confidence and go for a little bit bigger first serves, getting a few more free points."
Azarenka maintained a similar dominance over Aganieszka whom she has beaten in 12 of their last 15 meetings. She hasn't lost to the fourth-ranked Pole in almost two years.
Both players struggled to hold serve in the early stages, but Azarenka took control after breaking for 3-2 in the first set. She ran off eight of nine games, taking a set and 3-0 lead.
Down 4-1, Radwanska became more aggressive, making several forays to the net that allowed her to close the gap to 4-2. For a moment, there was a sense the Pole could stage another comeback as she did in the quarterfinals against Caroline Wozniacki.
Radwanska did make it 30-all in the eighth game, but Azarenka proved too strong, combining great net play and a potent backhand to end the Pole's threat.
"It was a little bit shaky in the beginning," Azarenka said. "I think I did a little bit too many unforced errors, rushed a little bit into the rallies. But I'm glad I could turn around quickly, start to be patient, start to be more aggressive and dominant, really going for my shots when there was an opportunity, and taking advantage of every short ball she gave me."
To win her second consecutive Qatar tournament, Azarenka admitted she will have to be more "consistent" and cut down on the errors. She had 35 winners against Radwanska but also 28 unforced errors.
Win or lose on Sunday, Azarenka will swap places with Williams in the rankings, a prospect that didn't seem to bother the Belarusian. She spent 19 weeks at No 1 in 2012 after winning her first Australian Open, gave up the top spot to Sharapova for four weeks and has been there since Wimbledon.
"There cannot be frustration, really. That's so out of my hands," Azarenka said. "I mean, I have been playing really well, I have been really consistent, I haven't lost a match yet, so why should I be frustrated? Ranking is ranking ... for me, it's always important to just win matches, win big tournaments like here, as well. If I'm No 2 after winning a tournament or whatever, that's what happens."