(Photo by Scott Barbour/Getty Images)

Fluctuating form, and assorted injuries have played havoc with the top few positions in the men’s rankings in recent months.

Roger Federer, knocked from his No. 1 residency by Rafael Nadal a year ago, and battling with back problems, began to drift precariously towards No. 3.

Then Nadal, hit by wayward knees, slipped back to No. 2 and dropped still further behind a surging Andy Murray.

Novak Djokovic, for all the world looking to take No. 2 in the spring, was instead overtaken on the blind side by Murray. He, in turn, now nursing a sore wrist, watched Nadal snatch back the No. 2 slot.

Normal service, for the time being at least, has now been resumed. The old faces have returned to their old positions, the same bums are on their old seats. Yet, three of them have been out of the tour with injury since Flushing Meadows, and two of those have postponed their returns for even longer.

The pattern is repeated in the next tier. Andy Roddick and Jo-Wilfried Tsonga, Fernando Verdasco and Gilles Simon, and Nikolay Davydenko and Juan Martin Del Potro, have boxed and coxed into roughly the same order that they held three, four, and five months ago.

And half of those six have also contended with injury.

Take Fernando Verdasco, who has postponed surgery in his attempt to qualify for the Masters Cup. Unwilling to lose the month required to recover from a persistent foot problem, he has headed to the Asian hard courts.

Davydenko himself pulled from a couple of tournaments this year with a persistent heel injury, though he has just won the Malaysian Open.

Meanwhile, Simon has clinched his first title of the 2009 after months of being plagued by a knee injury.

Further down again, in the ranking 20s, Tommy Haas will not return to the tour until Shanghai, and Sam Querrey will miss the rest of the year with an arm injury sustained in an accident.

Amidst all these fluctuating fortunes and frenetic on-court activity, two players have been absent since May, and will play little part for the rest of the year.

David Nalbandian has been out of the tour for hip surgery since May, though his No. 14 ranking has been protected. Also missing since May is Mario Ancic. Still fighting the after-effects of glandular fever, and without the benefit of a protected ranking, Ancic has yo-yoed between the Top 20 and No. 136 in the space of 18 months, and temporarily hovers at 77.

Both face huge obstacles to reassert themselves on the A.T.P.’s extraordinarily competitive ladder of ambition.

Can Nalbandian At Last Translate Talent Into Triumph?

Nalbandian had surgery in May due to a torn labrum in the hip, a cartilage that cushions the movement of the femur. It’s the same injury that both Gustavo Kuerten and Lleyton Hewitt suffered, and Nalbandian will take much solace from the comeback made by the latter since he underwent surgery.

Nalbandian reported on his website that he would need four months to recover from his operation before on-court training could resume, and did not anticipate playing the circuit again before the end of the year.

But, the latest news is that, subject to a satisfactory check-up in Barcelona, he may be able to play an exhibition match in mid-December. Another exhibition is planned for Buenos Aires a week later, which he hopes to use to build up his competitive form before rejoining the ATP circuit in January 2010.

He certainly seems to be remarkably upbeat about that return, “I still have plenty of time to play, and I keep my aim of retiring with a Grand Slam or a Davis Cup.”

Nalbandian’s creative and intelligent tennis is a great asset to the sport, but he has been criticised with increasing frequency for his inability to use his flair to make the transition from early rounds to the end of major tournaments.

He says, though, that pain has been a factor in his game for a year and a half. And prior to that, he was indeed beating the likes of Federer and Murray on hard courts.

Perhaps surgery will not only relieve him of pain, but also give him the renewed belief and enthusiasm to realise his potential more fully. If it does, Nalbandian has the knowledge, and experience of beating all of the current top four. Meanwhile the likes of Hewitt and Haas show that injury, and maturity are far from being barriers to renewed tennis success.

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