Then he won the Shanghai Masters, ripping apart the games of the two best players in the tournament: Novak Djokovic in the semis and Rafael Nadal in the final.
That won him a place in the World Tour Finals for the fifth successive year, where he defeated Rafael Nadal in the round-robin stage and earned his first win in 13 attempts over Roger Federer in the semi-finals.
He went on to win what was his 19th—and biggest—title from 24 finals, and the tennis spotlight at last shone on one of the most neglected talents on the men’s tour.
The serious, hard-working, slight man who shunned the life of Miami or Dubai for his home city of Volgograd, and who longed for the kind of support he saw lavished on his charismatic compatriot, Marat Safin, finally came out of his shell to enjoy the plaudits.
Riding a wave of confidence, his successes continued in 2010. He again defeated the world's top two players to win in Doha with some of the best tennis of his career.
In the first set of his semi-final against Federer, he put all 27 first serves into play en route to a 6-4, 6-4 win. In the final, he fought back from match points down against a rampant Nadal.
By now, there was even talk that maybe Davydenko could go all the way to his first Grand Slam title in Melbourne and, for a while, the dream looked possible.
He sailed through the first three rounds with ease but then hit the buffers in the shape of Verdasco. The Spaniard meted out the same treatment that he’d handed Nadal in 2009 and kept Davydenko on court through four hours and five sets of exacting tennis.
The Russian survived and, when he ripped apart Federer in the first set of the quarterfinals, it seemed for a moment that he might score three in a row against his bête noir.
The cruel mistress decreed otherwise and, by Dubai just three weeks later, there were signs that all was not well when Davydenko retired in the second round.
Worse lay ahead. He pulled out of Indian Wells, citing constant pain in his wrist. He even talked jokingly of trying to play left-handed to give himself some relief. The problem was soon revealed: a fractured wrist that took him off the tour for three months.
It must have felt like history repeating. Only the year before, riding high at No. 5 in the rankings, he was repeatedly forced off the tour with a foot injury.
Indeed he had to withdraw from the Australian Open, breaking a streak of 29 consecutive Grand Slam tournaments that dated back to the U.S. Open in 2001. That was also enough to take him out of the top 10—albeit for just 10 weeks—for the only time in almost five and a half years.
Now it looks as though he is destined to slip from the top 10 once again, only this time it is at the very time of the year when it means the most to be in the top eight. He is, in fact, in danger of failing to qualify for the year-end fireworks in London for the first time since 2004.
One problem is his court-burning run at the end of last year which has come back to bite him with a vengeance. He may still be No. 6 in the rankings, but unless he can defend the points he gained in the 2009 Asian swing, he is vulnerable to the chasing pack.
One of the pursuing hounds is Mikhail Youzhny who has just taken Davydenko’s Malaysian title. Another, David Ferrer, who has hardly any points to defend for the rest of the year, reached the semis of the same tournament.
The only consolation for Davydenko is that key challengers Verdasco and Tomas Berdych are posting poor results.
As well as a strong performance in Shanghai, therefore, Davydenko will need good results in the remaining European events if he is to reach his sixth consecutive WTF.
A good run in the Paris Masters, where he fell in the second round last year, might just do it. But time is getting short and, for admirers of the Davydenko brand of tennis, these are worrying times.
At his best, and that is usually on hard courts, he is able to play extravagant, extended rallies of surgical precision. He can use his hard, penetrating, technically-efficient ground strokes to open up the court and then inject killer shots down the line or cross-court.
He has the ability to take the ball early and generate blistering flat drives from the extreme margins of the court, and then pierce shot after shot at remarkable trajectories and acute angles.
During his 2009 autumn run, he also put to bed some of the frailties that had always dogged him before. Accused of lacking mental toughness, he won a final set tie-breaker against Djokovic and then went on to win a first set tie-breaker against arguably the toughest attitude in tennis: Nadal.
The consistency of his serve also turned a corner. His stats for 2009 showed a first serve of 69 percent, and in that final against Nadal in Doha, he served at 70 percent.
But since the summer, Davydenko’s crisp and energetic tennis seems to have deserted him and it does not appear to be solely due to his wrist.
He returned from injury just as the grass season began, and won a long, hard five-setter in the Wimbledon first round, losing in the second round only after winning the first set and losing two tight tie-beakers.
He went straight home to Russia to play the Davis Cup and again found the fitness to play a close match involving two tie-breakers against David Nalbandian. He then won a four-setter in his second rubber.
So the physical problems seemed to be behind him, yet the losses began to flow—in his first match in Stuttgart, his second in Hamburg, Umag, Toronto, and Flushing Meadows, and more recently in his first match in Kuala Lumpur.
So what has happened to dampen the confident, aggressive tennis that so excited the tour fewer than 12 months back?
In July came the unexpected news that Davydenko’s brother, Eduardo, would no longer be his coach. Unexpected, because theirs had been a long partnership dating back to junior years.
Even when Nikolay travelled to Germany before turning professional, his brother was his primary coach. Now Eduardo is intending to focus on the tennis career of his 17-year-old son, and Nikolay is looking for help from elsewhere.
The ATP website still shows Eduardo as coach, but the question hangs in the air: To whom will Nikolay turn when other coaches—Paul Annacone, Peter Lundgren, and Miles Maclagan—have all sealed deals with new charges? Can Davydenko regain that belief that he really does have the tools to beat the best?
A flicker of hope has illuminated his cause this week in Beijing, where Davydenko has reached the quarterfinals with a good win over another top 10 player suffering from a confidence-sapping streak, Marin Cilic.
In the process, Davydenko has passed a significant milestone: 400 ATP match wins. It’s an achievement worth celebrating and there are plenty of fans who hope the cruel tennis mistress will hand over to lady luck at this crucial stage in the Davydenko career.