After his four-set win over Philipp Kohlschreiber on Monday to reach the quarter-finals for the fourth year in a row, the Serb spoke eloquently and at length about the death of a woman he described as, "one of the most incredible people I ever knew" – his childhood coach, Jelena Gencic.
The world No1 was not told that Gencic, 77, had died of breast cancer until he came off court on Saturday night, having beaten Grigor Dimitrov in three sets, and he says his final conversation with her two weeks ago at her home in Belgrade has given him the "inner strength to push even harder" to win the tournament.
"Jelena was my first coach, like my second mother," he said. "We were very close throughout my whole life and she taught me a lot of things that are part of me, part of my character today, and I have the nicest memories of her. She dedicated all her life to the [younger] generation and to tennis. She never got married, she never had kids. Tennis was all she had in life.
"Before she passed away, she was giving lessons to kids last week. She didn't really care about the nature of the illness. She's one of the most incredible people I ever knew."
Summoning the steel that makes him a great player, Djokovic added: "I feel even more responsible now to [continue her coaching work] and go all the way in this tournament. I want to do it for her. The last conversation we had, two weeks ago, she told me, 'Listen, you have to focus, you have to give your attention to this tournament. This is a tournament you need to win.' [But] it's not about me only. There are so many great players still in the tournament."
The one who stands in Djokovic's way on his side of the draw, Rafael Nadal, with whom he duelled over two days in last year's sodden final, finally produced his A game to win 6-4, 6-1, 6-3 against 13th seed Kei Nishikori, the first Japanese man since Fumiteru Nakano in 1938 to reach the fourth round here.
It has been a tough tournament for the Spaniard. For the first time in his long French reign he has twice had to come from a set down – against unseeded opponents, as well – to get into the third round, where he found some form against Fabio Fognini. If we come away from this French Open with perceptions that differ from slams of recent years one might be that the game's acknowledged masters appear to be more vulnerable going into the second week than for quite a while.
As for Djokovic, it must be said that he was not as commanding against 16th seed Kohlschreiber as he had been in breezing through the first week, before winning 4-6, 6-3, 6-4, 6-4. He plays his second German in two days when the oldest player left in the tournament, 35-year-old Tommy Haas, steps up for what should be a quarter-final more charged than Monday's match. On Nadal's 27th birthday, Haas, the 12th seed, delivered another reminder that age is not just a number, it is a passport to knowledge. "I thought I played really well," he said of his three-set stroll against Mikhail Youzhny, who broke his umpteenth racket.
Ninth seed Stanislas Wawrinka came to Paris in good form but worrying about a thigh problem that forced his early withdrawal in Rome, and on Monday it let him down again. However, he threw away the bandages after losing the first set and dug in against Richard Gasquet to win a thriller, 6-7, 4-6, 6-4, 7-5, 8-6, finishing with a sumptuous forehand down the line. This was the fifth time France's eternal prodigal has blown a two-set lead in slams, and the sixth time Wawrinka has come back from two sets down, four of them in Paris.
Is Djokovic still the favourite? Maybe. Can Roger Federer, on the other side of the draw and in the absence of the injured Andy Murray, rediscover his faltering momentum to get past the rejuvenated Jo-Wilfried Tsonga on Tuesday, then into the semis and reach the final? Perhaps. Are the conditions finally moving Nadal's way? Without doubt. Will anyone outside the top four win the title? Unlikely. So, there is uncertainty in the air, and that has to be good for the tournament, good for the game – and not so comfortable for the heavyweights.
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image: © Mark Howard Photography