So much of the tennis season is spent prospecting, looking for the upward trends and vulnerabilities that will define the calendar. Sloane Stephens' big win over Serena Williams in Melbourne created expectations, but to this point, she has no more big wins.
It is mid-May, and Roger Federer not only has been beaten twice for the first time in three years by players who have never entered the top 10 (Julian Benneteau and Kei Nishikori), but so far he hasn't even been the best player from his own country. Switzerland's Stanislas Wawrinka is leading him in finals appearances this year (2-1) and titles (1-0).
Rome has come and gone. The French Open is less than a week away. And while there is intrigue as to whether Rafael Nadal, who just won another title in Rome, can defend 2,000 points from last year's Roland Garros title, whether Novak Djokovic can reach his singular goal of winning the French Open and thus securing both his career Grand Slam and the chance to corral all four majors in 2013, and whether we are finally seeing the real, inevitable decline of Federer, the real news is taking place not on the top shelf of the top 10, but in the crowded, unpredictable middle.
Suddenly, dangerously, only the big four could be considered even somewhat secure. David Ferrer, Tomas Berdych, Juan Martin del Potro and Jo-Wilfried Tsonga still aren't quite good enough to shake the elite, but they're too good to be consistently threatened by the rest of the field. However, each is vulnerable. Del Potro has been fighting injury and hasn't been healthy since beating Djokovic and losing to Nadal at Indian Wells. Wawrinka is this year's John Isner, aka "The Guy Nobody Wants to Play." Since losing an epic five-setter against Djokovic in Melbourne, Wawrinka has raised his level and with it his ranking. Over the past month, he has beaten Andy Murray (Monte Carlo), Ferrer (Portugal final), Tsonga and Berdych (both in Madrid), and is now just outside the top 10 at No. 11.
Wawrinka's charge underscores where the real jockeying is occurring, where the subset of players who should be called "The Vulnerables" live, and it might be the most exciting place in tennis. Over the past 18 months, Janko Tipsarevic, Isner, Nicolas Almagro, Mardy Fish and Richard Gasquet have shared the eighth through 10th slots, each at one point during the calendar a dark horse projected to make that leap into the penthouse space.
But Isner, overscheduled and unable to break serve, crested and fell in the first round to Denis Istomin. Not only is he out of the top 10, but the top 20, too, at No. 21. Fish hasn't recovered from his health trouble. Almagro has a 2-16 record in his past 18 matches against top-10 opponents, and the two victories have come against Tipsarevic, the only player in the space more vulnerable than he.
Tipsarevic, the Serb who played in the Barclays year-end championships in 2012, validated his great junior career by finally becoming a top-10 player last February. But he has been hanging on the edge for months, and his punishing five-set US Open quarterfinal loss to Ferrer might have been his peak.
Tipsarevic will be 29 next month, and like Ferrer, he is a middleweight whose game is based on a combination of athleticism and good-grade weapons without a great one. Unlike Ferrer, Tipsarevic has been saddled this year by bad losses, most recently to Daniel Brands in Munich (ranked 69th at the time) and Guillermo Garcia-Lopez (ranked 87th, in Bucharest). Tipsarevic is 11-10 but has returned to the top 10, replacing Wawrinka.
Tipsarevic hasn't reached the quarters of a 500-level or above tournament since retiring with a whisper to Jerzy Janowicz in Paris last November.
Tipsarevic is being squeezed, unable to beat the players in front of him but being severely challenged by young risers with bigger weapons like Marin Cilic and Milos Raonic. He has already lost to Ernests Gulbis and Grigor Dimitrov, the two fashionable names of the year. Perhaps the inexorable slide has begun.
The pattern is a familiar one: Players seem to have a short window to challenge the top before being attacked by the combination of their competitors and the pressure of having to defend points. Tipsarevic and Isner are fading out, Wawrinka is in, with the ageless Tommy Haas not far away from the top 10. Dimitrov, the Djokovic-conqueror in Madrid, and Gulbis, along with Raonic, seem to be the next men up.
With all the movement and topsy-turvy results with these formidable players, one thing is for certain: Cracking the big four doesn't seem like a realistic possibility.