Effectiveness without drama

ISTANBUL -- At the year-end WTA Championships on Thursday, Serena Williams and Victoria Azarenka met for the first time since last month's U.S. Open final. It wasn't as dramatic, yet Williams' 6-4, 6-4 win wasn't as straightforward as the score suggested.

Azarenka now needs to beat Li Na to secure a spot in the semifinals of the round-robin tournament.

Thoughts from Williams and Li's victories:

Serena's focus

As her serve faltered against Li on Wednesday, Williams couldn't help but exhibit her angst. She looked at her box, her racket and shook her head incessantly. No, the body language wasn't stellar.

That said, Williams knew she could get away with her mind wandering and serve not clicking against Li. Confronting Azarenka, there's little time to waste energy. Williams was quieter, didn't sulk, and for the most part, stuck to the task at hand to improve to 5-0 against Azarenka in 2012.

It was more confirmation that Williams is the true No. 1 and Azarenka's performance at the U.S. Open -- when she led Williams 5-3 in the third set -- bucked the trend. Williams has dropped one set against Azarenka all season.

"I'll probably have to play Victoria again," Williams said in a postmatch television interview.

She's right.

Azarenka, the clear second-best player in the world, should overcome Li on Friday. If she tangles with Maria Sharapova in the semifinals, as anticipated, odds are we'll get a Serena-Vika sequel in Turkey.

And another Williams win.

Williams' single-mindedness -- and two big serves -- aided her in reversing a 0-40 deficit at 2-2 in the first set.

Azarenka's own serve got her into trouble as she was broken for 5-3, then 6-4, handing Williams a combined four double faults.

For the second day in succession, Azarenka's racket went flying.

Her disappointment is understandable; Azarenka is desperate to prove she's a worthy No. 1 and knows losses against Williams diminish her ranking. She does, however, own a Grand Slam title.

Azarenka, through her play and a dip from Williams, usually makes the second set more interesting against the American, and when she raced to a 3-0, double-break advantage, a third set, ala New York, was on the cards. The fourth game was pivotal: Had Azarenka held, the set was over. But she was broken, the comeback was on, and a charging Serena is difficult to contain.

Williams will have even more of a mental edge if they do indeed battle Sunday.

Not serving notice

This should be one of the highlights of the season for Angelique Kerber. And it still might be after losing 6-4, 6-3 to Li to end her week at a somewhat misleading 0-3.

But the year-end championships can be a humbling experience. Facing the elite, weaknesses are cruelly exposed. Li's mental toughness (or lack thereof) surfaced again in her defeat to Williams. On Thursday, Li took advantage of a Kerber second serve that lacked pace and was more often than not conveniently placed -- for Li -- in the middle of the service box.

Kerber struck 28 second serves and won five points. Five. She hit eight double faults, including six in the first set and one on set point.

Not in the game plan.

Andy Murray's second serve is much better, and it was one of the reasons he ended his Grand Slam drought in New York last month. Rafael Nadal will never be categorized as a top server, yet Rafa, too, has improved his second serve (and he benefits from heavy spin). Kerber leaves Istanbul, probably destined for an island getaway, knowing she needs work in that area.

Her three-hour classic against Azarenka on Wednesday certainly helped Li, especially when the German -- playing in her tour leading 82nd match of the year -- lost the first set. She had nothing left. Unlike Azarenka, Kerber was playing for a third day in a row.

Still, a Li in full flow is a sight to behold. In one rally in the second set, she punished Kerber with a barrage of cross-court backhands until finally pummelling one Kerber couldn't touch.

Li said Wednesday that when she led Williams by a break in the first set, she realized she had a chance – and then started to overthink. Kerber's physical and mental state in the second set meant Li wouldn't blow this one. Further, Li heading into the match would have been comfortable given her 5-1 record head-to-head.

Can she oust Azarenka on Friday? Unlikely.