Serena and Venus Williams will clash at Wimbledon for the first time in six years on Monday, but the sisters' ferocious appetite for success suggests it might be premature to bill it as an emotional final fling. The sisters, who meet in the most anticipated fourth-round tie of the tournament, have reigned supreme for much of the last two decades at Wimbledon, lifting the aptly named Venus Rosewater Dish five times each. She's gone through so much that no one could even imagine. She never complained once. You have to give her credit for that Venus Williams on Serena With 27 grand slam titles between them, the siblings are well established as two of the greatest female players in history. Taking into account their incredible rise from the bullet-scarred courts of Los Angeles - a fairy-tale story that led father Richard to dub his children "ghetto Cinderellas" - only increases the magnitude of the sisters' accomplishments. But, given their array of interests away from tennis, it would be understandable if Serena and Venus, 33 and 35 respectively, were ready to skip the twilight stage of their careers in favour of more glamorous opportunities in the worlds of fashion and film. However, 17 years after their first tour-level meeting at the Australian Open, the sisters are still as competitive as they were when Richard first put a racquet in their hands as means to escape crime-plagued Compton. After a troubled period three years ago, when a serious foot injury and her lust for the celebrity lifestyle seemed to have taken its toll, Serena has been reinvigorated by French coach Patrick Mouratoglou - winning seven of the past 11 grand slams. A sixth Wimbledon title this year would mean Serena holds all four major titles at the same time and would put her on the brink of becoming the first woman since Steffi Graf in 1988 to win a calendar grand slam. Where do I start? She's done so much for this sport Serena Williams on Venus If she achieves that milestone, the world number one would also be within two titles of Margaret Court's all-time record 24 grand slams. "She's gone through so much that no one could even imagine," Venus said. "She never complained once. You have to give her credit for that." But, as Serena acknowledges, her glorious run should never overshadow Venus's own epic achievements on and off the court. While Serena took a while to fulfil her potential, Venus amassed four grand slams by the end of 2001. By the time Venus won her seventh and most recent grand slam, at Wimbledon in 2008, she was entrenched as the game's dominant force and emerging as an influential campaigner for equal prize money for women. "Where do I start?" asked Serena, when asked to chart Venus' legacy. "She's done so much for this sport." In 2011 Venus was diagnosed with Sjogren's disease, which often leaves her exhausted. The illness threatened to end her career, but Venus reached her first grand slam quarter-final since 2010 in Australia this year. Amidst all the glory, the sisters have still been dogged by controversy and tragedy. In 2003, their eldest sister Yetunde Price was shot dead in Compton. And, as two of the few black players on the tennis tour, Venus and Serena have sometimes been at odds with their peers. Besieged by allegations that results of matches between the pair were "fixed" by Richard, the situation became ugly at Indian Wells when Venus withdrew injured just before her 2001 semi-final against Serena. Playing the next day in the final against Kim Clijsters, Serena was loudly jeered, while Richard claimed he was racially abused. The Williams did not return to the tournament for 14 years until earlier this year. Despite those painful moments, the 26th meeting of the sisters' careers is a chance to toast the extraordinary longevity that suggests the sport's more fascinating family aren't done yet.