(CNN) -- They grew up together, have both been ranked world number one, and have nine grand slam titles between them. Now Belgian tennis stars Kim Clijsters and Justine Henin have a world record in their sights.
The duo will go head-to-head in the King Baudouin stadium in Brussels on July 8 in a match to launch Belgium's presidency of the European Union.
The arena holds 40,000 spectators, meaning the attendance is likely to exceed the current record for a tennis match -- the 30,492 who watched the "Battle of the Sexes" between Billie Jean King and Bobby Riggs in 1973.
Speaking exclusively to CNN, Clijsters said she was "extremely excited" by the prospect of an occasion which will be a celebration of Belgium and its two biggest sports stars.
"I will be emotional, exciting and historic," she said. "It will be a unique evening. Something historic for the sport of tennis and our country.
"I have been very fortunate to play in front of some amazing crowds during my career, none more special than my home crowd. Belgian fans are crazy about tennis."
The King Boudouin stadium is used by Belgium's national football team and hosts the annual Ivo Van Damme athletics meeting.
Some 34,000 tickets will be sold for the Clijsters-Henin match, with a further 6,000 invited guests.
Tennis legend King is set to be an honorary umpire at the match.
The Arthur Ashe Stadium in at Flushing Meadows in New York is the biggest venue on the professional tennis circuit, with a capacity of 23,000.
"The U.S. Open is the biggest stadium we have in tennis and the King Boudouin Stadium in Brussels is double that, so it's hard to imagine," said Clijsters. "I just hope everyone has a fun evening."
The July clash will be the latest chapter in a remarkable tale of sporting rivalry from a country boasting a population of just 10 million.
One-time roommates on grade-school tennis trips, Clijsters and Henin both reached the very top of women's tennis before surprisingly choosing to retire from the sport in their mid-twenties.
Clijsters made a stunning return to the circuit last year following the birth of her daughter Jada.
Having entered the U.S. Open as a wildcard, she stormed to the title, making her the first mother to win a grand slam since 1980 when Evonne Goolagong Cawley won Wimbledon.
Henin's comeback from a two-year hiatus in January was almost as spectacular. She progressed all the way to the Australian Open final before losing to Serena Williams.
Henin and Clijsters are tied at 12 wins apiece from their 24 meetings.
"It is extraordinary. It is almost surreal," Belgian Prime Minister Yves Leterme said in a press release about the match.
"When I talk to world leaders, whether it is in China or the United States, they talk about Kim and Justine."
Clijsters is relishing the prospect of renewing their rivalry and said although the match was an exhibition, both players would be out to win.
"It's amazing to have two players at our level come out of a country as small as Belgium at the same time. It's crazy," she added.
"We have grown up together, had a lot of our success at the same time and I think definitely pushed each other to improve.
"I have a lot of respect for her, what she has been able to achieve in her career and I have really enjoyed the two matches we have played since we came back. I hope this will be another nail-biter in Brussels."
While it may attract a bigger crowd, the contest is unlikely to carry the same political significance of King's encounter with Riggs in 1973.
King decided to take up the challenge after Riggs had come out of retirement at the age of 55 to beat another top female player, Margaret Court, a result he claimed proved the inferiority of the women's game.
The match was held in the Houston Astrodome on September 20, 1973 and had touches of pure theatre.
King entered the court in a red velvet chair carried aloft by four bare-chested college football players, before Riggs followed in a rickshaw drawn by a group of scantily-clad models.
King played a predominantly baseline game, shifting Riggs around the court before clinching a memorable 6-4 6-3 6-3 victory.