One of the pleasures that any sport affords is watching young talent—like sixteen-year-old Amanda Anisimova—arrive and triumph. Photograph by Adam Pretty / Getty

Big tennis tournaments have subplots. The BNP Paribas Open, in Indian Wells, California, is a big tournament (players and fans call it the “Fifth Grand Slam”) and already, before its final weekend, it has provided a couple of developments that have heightened the drama and given us a glimpse of where tennis—women’s tennis, anyway, and American women’s tennis, in particular—may be headed.

There was, of course, the return of Serena Williams after nearly fourteen months on maternity leave. She battled and scratched her way to wins in her first two matches, but, on Monday night, in a third-round match, could not get past an aging veteran, a player even older than she is, who blasted first serves and absorbed Serena’s pace to muscle groundstrokes back at her, flat, hard, and deep. That was Venus Williams, Serena’s sister, who is three months from her thirty-eighth birthday. Venus won again on Tuesday—in the late afternoon, the loveliest time for tennis in the desert, as the mountains to either side of the Coachella Valley darkened to purple above the stadium’s lip—defeating Latvia’s Anastasija Sevastova in two tight sets, and putting herself on a path to reach the women’s semifinals. (Speaking of subplots, it was at Indian Wells, in 2001, that Venus Williams withdrew from a scheduled semifinal against Serena five minutes before it was to begin, citing tendinitis; some fans believed that Williams’s father, Richard, had orchestrated her withdrawal so as not to have one sister defeat the other, and, after Richard Williams said that he heard racist comments during the final, the Williams sisters boycotted Indian Wells for years.)

Sachia Vickery might never have made it to Indian Wells this year were it not for the Williams sisters. A young American hopeful, she grew up, in Miami, idolizing them. Her mother, Paula Liverpool, took a second job tending bar in a strip club so that her daughter, a young teen-ager then, could continue to train and play tennis. Liverpool is a college-educated immigrant from Guyana, with no sports background, but Sachia had received free lessons from a local coach, grown serious about the game, and started riding Greyhound buses to tournaments. Last week, at twenty-two, she earned her way as a qualifier into the Indian Wells main draw, where she first defeated Eugenie Bouchard and then stunned world No. 3 Garbiñe Muguruza, before dropping her third-round match on Monday. Vickery is one of a handful of next-generation American women—none of them ranked in the Top 100 when the tournament began—whose play has formed the big reveal of this year’s BNP Paribas Open.

There was nineteen-year-old Caroline Dolehide, No. 165, a wild-card entry who won her first two matches, then overwhelmed world No. 1 Simona Halep, with forehands approaching a remarkable ninety miles per hour, in the first set of their third-round match—before tiring, fading, getting out-thought, and losing. There was Danielle Collins, another wild card, and one of those rare pros who played college tennis; she was a two-time N.C.A.A. singles champion at the University of Virginia. Now twenty-four, and ranked No. 117, she out-slugged the U.S. Open finalist Madison Keys to score the biggest win of her fledgling career, before losing on Tuesday. And there was Amanda Anisimova, daughter of Russian immigrants and a phenom at the age of sixteen. Yet another wild-card entry, she belted her way to three early-round victories, among them a straight-set upset of ninth-seeded Petra Kvitová.

On Tuesday, Court 2 was jammed for Anisimova’s fourth-round match, against Karolína Plíšková, the tall, lean, big-hitting Czech who reached No. 1 for a time last year. Anisimova is five feet eleven, and already possesses not only eye-popping power off of both wings but a feathery touch and a court sense beyond her years. In the first set of her match against Plíšková, experience trumped nerves. But the second set was as good as tennis has been in the Indian Wells Tennis Garden this year. It was, in a sense, the kind of tennis the Williams sisters more or less invented: first serves regularly reaching above a hundred and ten m.p.h.; step-in, big-swing groundstrokes from the baseline; swinging volleys from mid-court. Plíšková, her aggression more controlled, prevailed in a second-set tiebreak to win, but Anisimova, a junior champion, had announced her arrival.

She and the other emerging players—along with Keys, Sloane Stephens, and CiCi Bellis, who are already in the Top 50 and part of the tour establishment—suggest that American women’s tennis is in a very good place. Not quite Williams good, most likely—after all, there was only one Muhammad Ali, one Tiger Woods, one Michael Jordan. Venus and Serena have been that good: they are transcendent figures. One of the pleasures any sport affords is watching young talent arrive, improve, and triumph. Another is watching the greatest, like the Williams sisters, remain motivated, refine, retool. Enjoy them as their careers approach the end.