Khartoum, Sudan (CNN) The walls are lined with spectators as the sun hangs low in the sky. It is 5.30pm on a Friday at the wrestling arena in Hajj Yousif, Khartoum, Sudan and the air is thick with anticipation as two wrestlers circle one another at the center of the sand-filled ring -- bowed forward, with their eyes locked and foreheads just millimeters from touching.

The men wait for the perfect moment to lunge.

With one fluid motion, Mujahid, whose wrestling name is Arabic for "combatant," locks his opponent's arm, pulling him forward then moving away from under him. John Cena, named after the WWE icon, stumbles backwards. Dust rises as his back hits the ground, concluding the round and confirming his loss. Without missing a beat, Mujahid runs out of the ring and into the arms of his teary mother, one of the few women in the roaring stadium. Men come out of the audience with wads of cash and slap each congratulatory note to his forehead while folk music from his Nuba homeland blares in the background.

Wrestling has been a fixture amongst the Nuba tribes in South Kordofan, Sudan, for thousands of years. Far from just a game, it is a display of gallantry and valor so steeped in heritage that it served as the prime focus in a sensational photo series by Leni Riefenstahl -- a documentary filmmaker who once worked for Hitler -- catapulting the Nuba, in the 20th century, into cultural icons.

Now, as the Sudanese government wages a bloody counterinsurgency campaign in the Nuba's Mountain homeland, the sport has found another home in the government-built stadium in the capital. Even as its birthplace comes under attack, the spirit of Nuba wrestling is very much alive.

Big ambitions

The first tentative steps towards a new future came in late June as the sport's brightest and best boarded a 10,490 kilometer flight to Yokohama, Japan, where five Sudanese Nuba wrestlers have now completed rigorous training ahead of the Tokyo 2020 Olympics. The trip, part of the Wrestling Diplomacy project, is a joint venture between Japan and Sudan. Launched in August 2014, the initiative began with a visit from 23-year-old old Japanese wrestling coach Kosuke Sungawa, known by his wrestling name Suna.

Sent by the Japanese government to select and train prominent Sudanese Nuba wrestlers in Olympic rules, Suna, an Olympian, was trounced by the top local wrestler in what was meant to be a ceremonial "friendly" match to kick-start his second visit.

It was instead an awakening.

"I was filled with so much pride when Kiri, who I've been training for years, beat Suna," says wrestling coach Mustafa Hamad Ali. "The whole stadium was filled with electricity, everyone was so happy -- it felt like a blessing from God."

Cash is usually showered on wrestlers after they win the round.

Impressed and overwhelmed by the raw talent he'd found, Suna made his choice of five wrestlers for training in Yokohama from June 29 to July 31 -- three as players and two as coaches.

"Training was during Ramadan so we would train all day during our fast then finally eat at sunset around 7pm," Mustafa, who was one of the coaches, says with a smile. "It was tough but we persevered and are better for it."

The sheer determination shown by Mustafa resonates in the players that accompanied him. Isam Mohamed El-Hajj Hassan, known to his fans as Karabino, returns from Japan with two Olympic medals in his sights -- hopefully as early as the Rio De Janeiro games in 2016. Born and raised in Khartoum, the 18-year old is a living testament to how his Nuba traditions have transcended the mountains, competing from boyhood even within the capital.

"My family are in high spirits," says Karabino. "They are so happy to see me travel and work towards competing on an Olympic scale. They always come to watch me play and it makes me want to work harder," he adds. "Wrestling is not simply a career path. It's a matter of heritage."

The wrestling tournaments attract hundreds of spectators in Khartoum.

Ticket into stardom

While most relocate to the capital, many wrestlers head to Khartoum for months at a time before returning to their lives as farmers in Kadugli, South Kordofan at the end of the league. Making up to 2000 SDG ($329) per round, they are able to save up their earnings over a couple of months before returning home.

Historically, the sport served to build ties between tribes. Today, it has a similar purpose in Khartoum, bringing men from all over -- from Darfur to South Sudan to North Sudan -- into the melting pot of the ring where they emerge as local celebrities.