For a sizable portion of nearly two transformative decades, one family surname has competitively dominated tennis and continually inundated its news. Think about how an emerging generation of female players has never known a tour without the headlining Williams sisters, Venus and Serena. (Also read: Serena Williams chases calendar slam)
Some telling perspective on the subject from Garbine Muguruza, 21, who grew up in Venezuela and Spain:
"When I was 4 or 5, I turned on the TV, and they were playing," said Muguruza, Serena's victim in last month's Wimbledon final. "Today, I turn the TV on, and they are still playing.
"So I am saying, how is this possible?"
Who could resist occasionally posing that question since the late 1990s, when the sisters - born 15 months apart, African-American outliers from gritty Compton, California - began to lay siege to a sport historically and overwhelmingly trending wealthy and white?
Back then, there was resistance to the takeover. Nowadays, it is difficult to imagine women's tennis without Venus, 35, its elder stateswoman, and Serena, going on 34 and a U.S. Open title away from completing tennis' first calendar-year Grand Slam since Steffi Graf's in 1988.
The sisters do not need Clarence the Angel to remind them that it's been a wonderful sporting life, though not one without stumbles and setbacks. But the spectating world can grow impatient with the status quo, bored and resentful of its repetition. So let's consider what a Williams-less tour might have been like had Richard Williams, the family patriarch, never created his most improbable blueprint.
"In Serena's case, we would miss probably the greatest player of all time," said Patrick Mouratoglou, her coach, dispensing with the formality of her being one major title short of Graf's 22 in the Open era and three shy of Margaret Court's 24 overall. "But both of them have done so much for the sport because they have brought it to another level on the court and because, yes, of their story."
With his ex-wife Oracene Price, Richard Williams trained the tandem that has won 28 Grand Slam singles titles, 13 Grand Slam women's doubles titles, and a combined five Olympic gold medals in singles and doubles. With their global reach, Venus and Serena became the most impactful siblings in the history of professional sports, launching the century and their intrafamily rivalry by playing each other in six awkwardly tense Grand Slam finals between 2001 and 2003.
Though they are vastly different in demeanor, their combined narrative has connected tennis to a more mainstream sports culture, in a way Jimmy Connors and John McEnroe did for the men, for different reasons, back in their day.
The broadcaster Mary Carillo recalled watching the sisters during the opening ceremony of the 2000 Summer Olympics in Sydney, the objects of other picture-snapping athletes' affections.
"I was thrilled that it was two women's tennis players all these Olympians wanted to pose with, but it struck me that in their warm-up suits, Venus and Serena looked like they could have been any athlete," she said. "Pick a sport - track, basketball, volleyball."
Richard Williams has often cited a televised match involving the Romanian Virginia Ruzici as the motivation for envisioning a lucrative tennis life for his daughters.
"I'm glad he wasn't watching bowling that day," Carillo said. "If Venus and Serena had never played tennis, the game would have gone on. But they've changed it in so many ways."
The Williams Revolution
Most frequently, the sisters have been credited with the introduction of women's power tennis and the resulting surge of tall, hard-hitting players. While the counterargument can be made that the sport was destined, with or without them, to become more physical with the progression of technologically advanced rackets, there was more to the Williams revolution than size and strength, Carillo said.
"Martina Hingis and a lot of the others knew right away they couldn't beat Venus or Serena with power," she said. "But they believed they could beat them with craft. The reality was that Venus and Serena were also remarkable defensive players. They kept alive balls that no woman had ever kept in play."
A shade shorter than 5 feet 7 inches, Hingis was the queen of craftiness, the precocious Swiss Miss, when Venus and Serena hit the tour. Hingis angled her way to three Grand Slam titles as a 16-year-old in 1997 and became the sisters' early antithetical adversary, beating Venus in the 1997 U.S. Open final and losing to Serena in the final two years later.
Hingis had her successes against both, but she left the sport in early 2003, at 22, struggling with injuries and apparent burnout.
"The Williams sisters pretty much retired Hingis," said Craig Kardon, a longtime women's coach, who worked with Martina Navratilova and is now with American CoCo Vandeweghe. "There are still a few players with that style, counterpunchers, and they can certainly be top 10. But can they dominate? I doubt it."
For her part, Hingis said it was not one sister or both, but the depth of the tour that forced her out until an abbreviated comeback as a singles player in 2006.
"I had eight years, from when I was 14, and those years were very intense, tough, from 16 to 22," said Hingis, now 34 and a top doubles player. "I played 20 to 22 tournaments a year, and it's not like I was given any matches for free. You had to fight, run for your balls, and it's not like I could put in four serves, four aces in like Serena, and go home.
"From the quarterfinals, every week it was, you know, a load, the same players, not like now," she added, mentioning Lindsay Davenport, Jennifer Capriati, Monica Seles, Justine Henin and Kim Clijsters, in addition to Venus and Serena. Though Venus still plays inside or on the fringes of the top 25, she faded as a Grand Slam threat in recent years while dealing with the effects of Sjogren's syndrome, a chronic autoimmune disease. But Serena became "better conditioned in her 30s than she was in her 20s," said Carlos Fleming, Venus' agent, who cited a recent and muscularly stunning New York Magazine photography spread as visual proof.
Kardon compared Serena to Navratilova in her willingness to "demand more of yourself and the people around you, pay the price." On the other side of 30, he said, Serena "got a taste of success far beyond what she envisioned, of what it would be like to make history, and as with all truly great champions, that drove her to push herself even more."
Never one to mince words, Serena once mocked the No. 1 ranking of a now retired Russian, Dinara Safina, who had not won a major. Safina was not alone in that category, which includes the still active Jelena Jankovic and Serena's good friend Caroline Wozniacki.
WhileÂ receiving an award recently in Toronto, Henin - who was probably Serena's most challenging opponent, besides the younger Venus - predicted that Serena would win the calendar Slam, saying, "What I admire and respect so much still is that Serena remains the boss."
But Henin added that the rest of the current field had become too interchangeable, too timid.
"There are many girls that can play good tennis, but it's not consistent enough," she said. "I wish the girls can be more consistent and believe that they can beat Serena, because some players proved in the past that it is possible."
Agnieszka Radwanska, the Polish star who has reached No. 2 but has failed to beat Serena in eight tries, including in the 2012 Wimbledon final, said that having many different players in the later rounds of tournaments might actually make the sport more interesting, even if Serena has been every major tournament's overwhelming favorite.
"In men's tennis, we see the dominating thing, the three or four guys being there all the time, and you can see the same semis or the finals every time," Radwanska said. "What is better? That is the question for fans."
Fleming, Venus' agent, argued that Serena's more recent dominance, with her winning eight majors after turning 30, "puts her in the conversation with people like Jordan and Ali, among the greatest professional athletes."
Like Muhammad Ali, she has also had a polarizing public effect, given lingering disapproval of the family's early methodology and her own on-court machinations and confrontations, most notably with a lineswoman in the 2009 U.S. Open semifinals.
The anti-hero - especially one as physically dictating as Serena - can be a marketing sensation and savior, too. Without her to root for or against, the women's game may well have endured a prolonged desultory period, especially in the United States.
"The truly great ones have always been different, had something special inside," Kardon said. "We can guess all we want about what it would have been like without the sisters. The fact is they're here, and their longevity has been amazing."
'Our Greatest Ambassadors'
Outside the lines, Venus and Serena's perseverance has allowed them to become "our greatest ambassadors," said Katrina Adams, the first former tour player and African-American to lead the U.S. Tennis Association as its chairman, chief executive and president.
"They were very sheltered coming out and actually up until they were in their 20s," Adams said. "But it also shows the beauty of their evolution as women. I would wish for every female athlete to realize such growth and independence."
It once was projected that Tiger Woods would herald a new era for golf, drawing men of color into his sport. That has not really happened, but some of the most promising American women's tennis players in recent years - Sloane Stephens, Madison Keys, Taylor Townsend - are black and have spoken of being inspired by Venus and Serena.
Mouratoglou, who is from France, said the sisters had been global socioeconomic game changers.
"Because of their success and charisma and because they come from Compton and got so much publicity, and this is not just in the States," he said. "They made people know that anyone that comes from anywhere, rich or not, can play and be successful."
Together and individually, the Williams sisters built a platform from which to set an agenda on a variety of issues. In her prime winning years, Venus quietly became the tour's social conscience, campaigning for - among other things - equal prize money at Wimbledon and the French Open.
"She became the spokeswoman at a time when there was a huge vacuum after the leadership years of Chrissie and Martina," Carillo said, referring to Chris Evert and Navratilova. "Steffi dropped the ball on that. Monica dropped the ball. Venus understood that the baton had been passed to her."
For all those who had their shots at the Williams sisters and moved on, Fleming believes the most compelling and commendable relationship - the one women's tennis would have most missed without the sisters - remains the bond between Venus and Serena.
"In the early days, they would play each other in a final and go back to a hotel suite they shared, and there would be flowers waiting for the winner," Fleming said. "Imagine what that was like. And to have Venus, who was such a standout, have a member of her family exceed her in the way Serena has, and the relationship stayed intact, actually strengthened, it's almost sad to think of the sport not having had the example they set under that kind of pressure."
As Venus grapples with career mortality, Serena enhances her tennis immortality. They have come a long way since Hingis, who has returned to the game as a doubles champion and a mentor to Belinda Bencic, a rising 18-year-old Swiss player who upset Serena in the Rogers Cup semifinals in Toronto this month.
In much the way Hingis once did, Bencic worked the angles, frustrating Serena with counterpunching and craft.
Bencic, the new Swiss Miss, was 2 when Serena won her first Grand Slam title, on the hardcourts of Arthur Ashe Stadium. Now Bencic may be one of a few with a chance to upend the next phase of the Williams legacy.
"It's been a great run, a great ride," Adams said. "We do know it has to end eventually."
Not just yet, perhaps not soon. How is this possible? The better question would seem to be, What in the world would women's tennis have been without them?