Can the man who knocked out Murray go on to challenge the Greatest?

While it would be absurdly premature to herald this as the moment the standard of men's tennis was handed over to a new guard, it is inescapable that the absence from the final of Roger Federer and Rafael Nadal has given it an aura that extends beyond mere novelty.

Not since Marat Safin triumphed in the Australian Open three years and 11 championships ago has a Grand Slam men's singles title been claimed by somebody other than Federer or Nadal.

Today a little bit of history can be made and a new name added to the champions' roll of honour.

Both Djokovic, the 20-year-old Serb, who bears a striking resemblance to a young Muhammad Ali, have stories to tell.

Djokovic's journey has taken him from war-torn Belgrade to a day when the streets of his home city will empty as millions of his countrymen settle before their televisions to watch his attempt to capture Serbia's first major tennis title.

Tsonga, meanwhile, has conquered the injury problems that blighted his early career to become an unseeded, theatrical attraction and a man whose stature has grown with every moment since his first-round demolition of Britain's Andy Murray, the No 9 seed, two weeks ago.

Just seven months previously, Tsonga, then No 178 in the world, was engaged in winning a small-change challenger tournament at Surbiton, in Surrey, while Nadal was concluding his third consecutive tour de force at the French Open championship in Paris.

Three days ago, the Frenchman's power, athleticism and fearless tennis in the Rod Laver Arena reduced Nadal's reputation to rubble.

The departure of Federer, at the hands of Djokovic, and Nadal represents a seismic shift at the game's core, as Tsonga acknowledged when he said: "Tomorrow is going to be a big moment of sport."

An understatement if ever there was one.

Whoever triumphs this morning will surely lay claim to become the next challenger to Federer, the greatest tennis player of modern times, and Nadal.

Understandably, Dijana Djokovic is convinced that her son, the boy who learned to play through the dark days of Belgrade's history, is at the defining hour of his embryonic career. "Tsonga is very good but now my son has beaten Federer, it's out of the question that he can lose," she said.

Team Djokovic — Novak's parents, Dijana and Srdjan, and brothers Marko, 16, and 13-year-old Djordje — will be at courtside again to support the man they know by his family name, Nole.

Tsonga will also have family backing, his parents, Didier, who was born in the Congo, and Evelyn, arriving here from France this morning.

Yesterday Dijana Djokovic spoke of the hardship and fear that her family endured in shaping the oldest of her three sons into a champion-elect — and of the dramatic effect on her homeland of the new generation of Serb tennis stars.

"Tennis is like a virus sweeping across Serbia," she said. Ana Ivanovic may have been defeated by Maria Sharapova in the women's final yesterday, but her rise to No 2 in the world, added to the prominence of Djokovic and Jelena Jankovic, a semi-finalist at these championships, means Serbia, a nation of 8.5 million people, is punching way beyond its weight.

"I've been told that when they have been playing no one at home has been going to work, or going to school!" said Dijana.

Yet as she absorbed the scale of her son's achievement in reaching the men's final, she also recalled times when the streets of Belgrade emptied for more deadly reasons.

She will never forget the nightly air raids during the 78-day NATO bombing campaign against the tyranny of Serb president Slobodan Milosevic in 1999.

For 17 years, she worked with her husband in the pizzeria they still own in the mountains, a couple of hours' drive from the city. But they had been in Belgrade when the bombs rained down from NATO's planes.

Defiantly, the Djokovics refused to retreat to the underground shelters.

"We went to the shelters only once," she said. "I knew that I'd go crazy if I ever went back. I thought: 'If the bombs are going to hit me, I don't care any more'.

"Each day we went to the tennis court from 10am till 6pm. The kids were playing tennis and we were sitting and laughing, drinking coffee and having lunch. And then we'd go home to sleep.

"This is how we spent the bombing. It's not easy to remember this. Some of the bombs landed just a kilometre away from our street — you never knew what could happen. But tennis kept us sane."

The rise of Djokovic to No3 in the world, has brought the family enough wealth for them to plan building their own tennis academies, one in Belgrade with a second in the heart of the country.

"Tennis is our business now," said Dijana.

The family are unmissable in their support for Djokovic, sitting by the side of the court wearing tracksuits bearing the four letters of his nickname.

"Nole needs us here because he is away so much that he feels nostalgic for his family and this is a time we can support him," said Dijana. "He's tired of being alone. I cook for him and Nole plays with the boys. He likes to chill with his brothers, who both want to be like him. There are moments when Nole is still my little boy but he is maturing in how he sees life and what he wants from life."

The success of Djokovic, and Ivanovic and Jankovic, has done more to sell Serbia's post-Milosevic existence than a governmentsponsored advertising campaign on CNN.

"It's true, tennis is giving a new, beautiful image of our country," said Dijana.

Her son's contribution cannot be underestimated. Djokovic defeated Federer at his own all-court game, one built on immense power and belief.

"Nole beat Federer with his own weapons, just as my husband said he would after Roger had defeated him in the US Open final last September," said Dijana. "Nole is my champion, whatever happens in the final here."

Her son, a week younger than Murray and a friend of the British No 1 from their days on the junior circuit, has also endeared himself to crowds around the world with his impressions of other players, including Sharapova, Nadal and Andy Roddick.

Yet, critically this past fortnight, he has delivered the impression that he has the credentials of a champion.

Now only Murray's conqueror stands between Murray's friend and a major step towards greatness.