Djokovic vs. Berdych:  Since the start of 2011, Djokovic has lost only five matches outside Davis Cup and the year-end championships.  While one of those defeats came in a final (via retirement), the remaining four all arrived at the semifinal stage.  At first glance, the world #1 would seem secure from a fifth stumble in the penultimate round, for he has lost only one of his nine previous meetings with Berdych and none of the last six.  Never has this pair met on clay, a surface that should tilt in Djokovic’s favor because of his supple movement, greater margin for error, and more patient approach to constructing points.  Moreover, his most fearsome weapons (return of serve and backhand) mirror the Czech’s greatest strengths (serve and inside-out forehand), so the latter’s tactics play into the former’s hands.

Yet Djokovic has looked distinctly mortal this week at the only first-half Masters 1000 tournament where he has not won a title.  Clearly shaken by the death of his beloved grandfather, he has lacked the relentless focus that has defined the last 16 months.  Against the unremarkable Robin Haase, the Serb dropped four of nine service games a day after losing a 6-2 set to Dolgopolov.  On the other hand, Djokovic did display a flash of his familiar killer instinct when he seized command of his encounter with the Ukrainian at 4-4 in the third set, earning the decisive break with stirring defense and then serving out the match with ease.  As he acknowledged after his quarterfinal, the top seed cannot afford to waver in focus when he faces Berdych, who faced just one break point throughout his three-set victory over Murray, one of the ATP’s best returners.  In fact, his statements exuded little confidence but rather an ominous note of resignation, often a signal of an uninspired effort by the Serb.  At some level of his consciousness, he may not want to face Nadal at a moment when his deflated emotions would render him vulnerable to a momentum-slowing setback in their rivalry.

Although his strengths do not fit the traditional profile of a player dangerous on clay, the Czech does relish the additional time to set up for his bone-crushing groundstrokes and the opportunities to shield his backhand.  Not for nothing did he come within a set of the Roland Garros final in 2010, closer than Djokovic ever has come to that elusive prize.  Whereas his semifinal foe enjoyed a relatively comfortable route to the weekend, Berdych dispatched a trio of talented and contrasting opponents in Cilic, Nishikori, and Murray.  That sequence of tests will have built his consistency and more importantly his self-belief, already restored by an outstanding Davis Cup performance after a tepid month at Indian Wells and Miami.  Contrasting with the gloomy mood of Djokovic is this positive energy, which could help the Czech overcome his history of futility against his nemesis.  While the record illustrates the world #1’s stiffer competitive resilience, Berdych showed some notable grit of his own by rallying from losing an epic first set against Murray to dominate his higher-ranked opponent thereafter.  Not the most convincing player with a lead, he has won the first set in four of his last seven battles with Djokovic, only to watch three of those four matches slip away.  As long as he can start the match in imposing fashion, however, Berdych should feel confident that he can stifle the resistance of a champion not fully invested in the task at hand.

Simon vs. Nadal:  Dominant in his clay meetings with Ferrer, whom he dispatched in last year’s Monte Carlo final, Nadal now faces an opponent with essentially the same playing style and a much lower level of clay expertise.  Of the fourteen sets that they have contested, all on hard court, the Spaniard has won twelve in a demonstration of his clear superiority in nearly every dimension of the game.  Lending a breath of intrigue is the fact that the two sets won by Simon came in the same match, a stirring three-hour upset of the then-world #1 at his home tournament in Madrid.  That 2008 duel remains the highlight of a career without any other Masters 1000 finals and only one title above the 250 level.  While four of his nine career titles have come on clay, hard courts better suit the Frenchman’s game by injecting more pace into his smooth, steady, but not explosive groundstrokes, which cannot hit through Nadal’s defenses like the flatter missiles of a Djokovic, Soderling, or Del Potro.  Perhaps emboldened by a unexpected quarterfinal appearance at Indian Wells, Simon scored consecutive victories over top-10 opponents for the first time ever en route to reaching his first career Masters 1000 semifinal on clay.  Most atypical among his compatriots, this Frenchman has overachieved considering his modest talents and unassuming manner.  All the same, his victories over Tipsarevic and Tsonga resemble minor ripples compared to the tsunami that he would trigger should he halt Nadal’s 40-match winning streak in Monte Carlo.

As he usually does following an injury, Rafa let murmurs trickle through the press about his lack of practice and general feelings of vulnerability as he prepared to defend a title that has not left his hands since 2005.  To the surprise of few, those murmurs meant nothing more than they usually do as the world #2 has cruised through his first three matches without encountering significant adversity.  Most alarming from Simon’s perspective, two of those three victims played an especially high level of tennis by their standards but still could not scrape a set away from the Mallorcan.  Over the last several years, of course, only Djokovic and occasionally Federer have managed to emerge from a clash with Nadal with anything more than a moral victory based on the sense of having competed gallantly in defeat.  More often than not, Simon bravely confronts even the most intimidating challenges, such as the towering Isner in an Indian Wells quarterfinal that he nearly stole from the home favorite.  But the indefatigable counterpuncher ultimately fell short on that occasion, and only a miracle will prevent him from falling short here.