The first notable tournament of the Asian fall season, Tokyo in its early stages featured notably lackluster tennis between players jaded from the long season.  Double faults have run rampant, feet have moved sluggishly, and body language has looked tepid.  Now that the critical stages have arrived, however, spectators can hope for that trend to change.  We preview the diverse group of quarterfinals at this Premier Five tournament.

Errani vs. Petrova:  Well aware that her second serve dangles a tempting invitation to opponents, Errani protected her greatest weakness by serving at 80% through her first two matches.  The Roland Garros finalist no longer needs to prove herself on hard courts after reaching a semifinal at the US Open, in addition to a quarterfinal in Melbourne before her breakthrough in Paris.  Against Bartoli, an outstanding returner who should have mauled her serve, she struggled to hold for the first set and a half but found the competitive resilience to turn the tide.  Once she did, Errani cruised to victory with much less drama than her quarterfinal challenger endured.  Also impressive at the US Open, where she won seven sets, Petrova managed to outlast rising star Petra Martic on Wednesday in the longest match of the tournament.  Splitting tiebreaks in the first two sets, she pounced alertly to claim an early lead in the final set that she nearly but not quite relinquished at the end.  After those 191 minutes of tension, however, the 30-year-old veteran may lack the energy or patience to cope with Errani’s versatility.  While her 15 aces dazzled at first glance, a first-serve percentage below 50% probably will not earn her sufficient free points to compensate for the Italian’s advantage in the longer exchanges.  Earlier this year at the Australian Open, Petrova succumbed meekly to the woman who has risen to #7 in the world during a season that has surpassed anything in her imagination. 

Sharapova vs. Stosur:  Perhaps fortunate to escape her notorious nemesis Schiavone, the Australian trailed by a set and later by a break in the third set before she edged through that encounter.  Having shed the rust that perhaps clung to her then, Stosur played a much more convincing match against the less intimidating Cibulkova, dominating behind a serve that she never dropped.  Despite the fast surface, she still found ways to construct points around her forehand more often than one might have expected, and the efficient victory should have saved her vital stamina for the tournament’s later stages.  Stosur will need that stamina to overcome the balance of power in a strikingly lopsided rivalry with her quarterfinal opponent, who has captured 10 of their 11 previous meetings in often overwhelming fashion.  But the underdog’s lone success came during the post-US Open fall season, at the 2011 year-end championships, and she appeared to build upon that momentum shift to nearly repeat the feat on the indoor clay of Stuttgart this spring.  In perhaps the best WTA match of the year, Sharapova saved a match point late in the second set before earning the triumph that, more than any other, launched her towards that historic moment in Paris.  Consistently inconsistent in her opener against Watson, the four-time major champion sharpened her weapons significantly to avenge an earlier loss inflicted by Safarova.  If both women found the level that they showcased in Stuttgart, the quality of play in this hitherto lackluster week should rise a notch, or two or three.

Azarenka vs. Kerber:  Close to her 60th victory of a peripatetic season, Kerber has not paid the price for a busier schedule than most players of her newfound level.  She encountered no significant resistance in her first two Tokyo matches, able to rebound from a disappointing fortnight in New York.  A more capable mover than her size would suggest, Kerber counterpunches by nature but can attack when the opportunity presents itself, as a semifinal appearance at Wimbledon proved.  Although Azarenka has defeated her twice in straight sets this year, she stayed competitive through most of both matches and strung together a few sequences in which she outmaneuvered the world #1 from the baseline.  Only two players have solved Vika on her favorite surface in 2012, one of them Serena in an epic US Open final, so the challenge looms large for Kerber.  All the same, Azarenka’s form sometimes has dwindled in the fall, and one wonders whether she will need to confront memories of her heartbreak in New York should Kerber stay within range again.  Through two matches, the top seed has conceded just eight games in her usual early-round declaration of intent, and she handled the crafty Vinci with ease on Wednesday.  In the absence of Serena and Kvitova, Azarenka becomes the clear favorite to win every hard-court tournament that she enters, so the pressure rests on her for the rest of this week.

Radwanska vs. Wozniacki:  Outstanding in the first half, the Wimbledon finalist suffered a perceptible decline during the second half with early losses at the Olympics and US Open as well as the two Premier Five tournaments in North America.  Doubtless glad to avoid Li, who inflicted both of the latter setbacks, Radwanska faces an equally stern test in a possibly resurgent Wozniacki.  On an unexpected eight-match winning streak after she lost in the first round of the US Open, the Dane still can harbor hopes of qualifying for the year-end championships but must plow deep into both Tokyo and Beijing.  Her three-set comeback against Li last night represented arguably her finest victory of the year, and certainly her best since upsetting Serena in Miami.  Halted by the Chinese star at marquee moments before, Wozniacki should have gained confidence from that victory that will help her against a rival whom she has dominated.  Before Radwanska narrowly defeated her in Sydney this year, she had won five consecutive meetings with her friend and fellow counterpuncher.  Now that the tables have turned in 2012 regarding their overall success, the world #3 seeks to impose that change upon her rivalry with the former #1.  Despite games seemingly at odds with the fast surface, each has won Tokyo before en route to completing the Asian sweep in Beijing.  Expect plenty of long rallies from women who often compile microscopic totals in both winners and unforced errors.  Against the rhythmic baseline defense of Wozniacki stands the arrhythmic craft of Radwanska, the most imaginative player in either top 10.