As the tremors from Berdych’s quarterfinal upset reverberate through New York, the remaining four quarterfinalists take center stage in New York.  Now the clear favorite to win a fourth consecutive hard-court major, Djokovic hopes to avoid the same fate as Federer against a similar opponent.  First, however, comes an evenly balanced match between two of the ATP’s forgotten men.

Tipsarevic vs. Ferrer:  Bracing for their first meeting since 2008, these two veterans have played the best tennis of their careers over the last twelve months.  While Ferrer has reached the quarterfinals at every major this year and the semifinals at Roland Garros, Tipsarevic now has complied consecutive US Open quarterfinals as well as semifinal appearances at two Masters 1000 tournaments since last year.  Gifted with an especially tranquil area of the draw after Nadal withdrew, these two small men have not failed to capitalize on their opportunity.  While Tipsarevic has won twelve consecutive sets after falling behind his first opponent by two sets to love, Ferrer has surrendered only one set in four matches.  Neither thus has experienced meaningful pressure on the scale of a match as a whole, although each has played several tightly contested sets.

Among the keys to this match is the Serb’s ability to establish himself in service games.  One of the three best returners in the ATP, Ferrer excels at blunting the power of first serve and maneuvering himself into a rally. Since he should produce greater consistency than Tipsarevic, he will fancy a match of long points that rewards his fitness and high-percentage shot selection.  But the fourth seed must take care that his indifferent serve does not undo the benefits of his return, for he struggled mightily on serve throughout his victory over Gasquet.   The Serb should prove more capable of capitalizing on such openings presented them than did the Frenchman, and one can envision a match of several miniature momentum shifts.  Skilled at redirecting the ball with both groundstrokes, Tipsarevic will aim to finish points by firing shots down the line over the high part of the net, whereas Ferrer favors his inside-out forehand as his premier weapon to finish points.  Since both men cover the court effectively and lack ferocious offense, though, most points probably will end on forced or unforced errors rather than clean winners.  A sturdier competitor than Tipsarevic except against the top three, the Spaniard has accumulated much more experience at this stage of prestigious tournaments and should find the confidence to stay positive more easily than the Serb in what promises to become a war of attrition.

Del Potro vs. Djokovic:  On Wednesday, Berdych used his size and raw power to hit a five-time US Open champion off the court in thunderous fashion.  On Thursday, Del Potro will hope to deploy the same weapons against the defending US Open champion.  This quarterfinal marks their third meeting of the summer, following straights-sets victories for the former at the Olympics and for the latter in Cincinnati.  Never had Del Potro solved Djokovic before that bronze-medal match, which culminated a disastrous week for a man who had raised his (and his nation’s ) hopes for a medal so high.  Refusing to wallow in the disappointment, and perhaps drawing motivation from it, the Serb avenged the loss authoritatively on the hard courts where he has compiled a perfect record against the Argentine, retirements aside.  Although they did collide here five years ago, the Tower of Tandil had not yet matured into a poised competitor, so Djokovic can expect fiercer resistance this time. 

Or should he?  Since returning from wrist surgery, Del Potro had not defeated any member of the top three until the bronze-medal match.  And a left wrist injury appeared to hamper his backhand during the Cincinnati rematch, an important stroke for him to assert himself in rallies with Djokovic.  Repeatedly running around his backhand to hit forehands, Del Potro ultimately surrendered too much court for his fleet-footed opponent to target with his counterpunching.  The best returner in the ATP, Djokovic has not looked quite as otherworldly in that department as he did at the 2011 US Open, but he still should force the 2009 champion to play more points in his service games than did his previous victims.  Enjoying a more routine progress into the quarterfinals, the second seed has spent barely six hours on court through four matches and played barely two uneventful sets on Wednesday when Del Potro played three sets of much greater drama and emotion.  Already superior in fitness, Djokovic should recover more smoothly for a third consecutive day of tennis, although his game itself requires more energy to execute consistently.  Nevertheless, the lack of quality competition appeared to leave Federer unprepared for the elite effort summoned by Berdych, and the same problem of meager preparation might afflict the Serb when the level of resistance rises sharply.  As a weekend of consecutive best-of-five matches looms, though, Djokovic probably would prefer the risks of excessive rest to the erosion caused by excessively arduous encounters.  Conceding no more than seven games in any of his matches, none of which have reached the two-hour mark, he should frustrate a somewhat jaded Del Potro with his explosive athleticism and seamless transitions from defense to offense.  Although the moment for revenge has passed, Djokovic learned at the Olympics that this rival deserves his full attention, so his consequent wariness should sharpen his focus and facilitate a victory perhaps more straightforward than his fellow champion’s credentials would suggest.