Sunny Hale, an American polo player whose peerless style and audacious speed made her the country’s top ranked woman in the sport and who was rated among the best athletes of any gender ever to play the game, died Feb. 26 at a hospital in Norman, Oklahoma. She was 48.

The cause was complications from breast cancer, said a sister, Stormie Hale.

Hale had a career of firsts: She was the first woman to play on a team to win the prestigious U.S. Open Championship; the first woman to be named the MVP of multiple top-flight tournaments; and most notably the first woman to receive a five-goal handicap, a rating that placed her in the upper echelons of the sport’s American professionals.

Hale, who learned to ride horses before she could walk, began her career in the late 1980s when she dropped out of college after the temptation of a life of polo proved too alluring. She once described her decision as a woman to turn pro as risky in a game dripping with machismo.

The majesty of polo has seduced British princes, exhilarated Hollywood actors and inspired works of literature by Rudyard Kipling and Jerzy Kosinski. For generations, however, the “sport of kings” was inhospitable to women.

When Kipling published the short story “The Maltese Cat” in 1895, ladies were restricted to riding sidesaddle, if at all. And in 1972, when Kosinski was writing the first drafts of “Passion Play,” his novel about a hypersexualized traveling polo pro named Fabian, women were not allowed to play in competitive U.S. Polo Association tournaments.

Hale was a second-generation player. Her mother, Sue Sally Hale, had helped integrate the sport in the 1950s and 1960s through elaborate ruses: long hair stuffed into her hat, a form-disguising shirt and mascara on her upper lip to create the look of a mustache.

With changing attitudes, Sunny Hale was able to avoid such deceptions.

She drew international renown as a female professional who played the game better than the vast majority of men she met on the field. Her smooth swing of the mallet, fearless poise astride the saddle at a full gallop and astute mind for strategy also gained her the respect of polo’s elite pros including Memo Gracida, Eduardo Heguy and Gonzalito Pieres.

A testament to her prowess came in 2000 when Adolfo Cambiaso — the Argentine widely considered the greatest player the game has ever seen — personally selected Hale to join the acclaimed Outback Polo Team for a run at that year’s U.S. Open Championship, the sport’s American equivalent to the Super Bowl.

In doing so, Cambiaso passed over scores of other — entirely male — prospects, including those who had a higher rating. At the time, Hale had a four-goal handicap when the team had an opening for a five-goal player.

“For Adolfo to choose a four-goaler to fill a five-goal spot meant that not only the best four-goaler over all the men, but also the best five-goaler and the only one he wanted on the team,” said Tim Gannon, the founder of the Outback Steakhouse restaurant chain and a longtime polo player and owner of the Outback team.

In polo, players are rated from -2 to 10. In the sport’s modern history, only a few dozen out of tens of thousands have achieved the coveted 10-goal handicap.

Cambiaso, a 10-goaler since he was 17, said that despite Hale’s lower handicap he considered her his equal when it came to strategy.

“She had the head of a 10-goaler,” Cambiaso said. “I needed somebody who was intelligent . . . That’s why we won.”

Phil Heatley, a board member of the National Polo Museum who also played on the Outback team in 2000, said that Hale at her death was nominated to the museum’s hall of fame in part for her role as the first woman to win the U.S. Open.

Sunset Hale was born in Carmel, California, on Dec. 30, 1968, and grew up on a farm surrounded by horses. She recalled spending afternoons sitting on top of her pony drawing in her coloring books.

She was a precocious young rider. “Mom constantly would have to tell her to slow down,” Stormie Hale said. “She’d always go faster, go faster.”

Her mother, the first woman admitted as a member to the U.S. Polo Association, died in 2003.

Besides her sister Stormie of Monterey, Calif., survivors include her father, Alex Hale of Carmel; another sister, Dawn Hale of Fresno, Calif.; and a brother, Trails Hale of Simi Valley, Calif.

She enrolled at a community college in Moorpark, Calif., but dropped out, she once said, after looking down at her notes in a psychology class and realizing all she had written down referred to polo.

Turning pro at 18, she encountered resistance on the field and off.

“I’ve had guys say they’re going to run me over, going to kill me,” Hale told Sports Illustrated in 1997. “I’ve been called every word in the bad-word dictionary. I’m in a sport where it’s more common for men to be good than for women. So I’m going to take some criticism. And I’m willing to take that. I’m more interested in playing a good game than reacting angrily to someone who’s just being chauvinistic.”

Maureen Brennan, the owner of the Goose Greek polo team based in Upperville, Virginia, said that as a player, coach and mentor, Hale influenced a generation of women in polo.

“She always said, ’The team is not me — we are the team,’ “ Brennan said. “She was not ever selfish in what she learned. She shared it all. She gave it away.”

Hale established a women’s championship polo tournament and worked with the U.S. Polo Association to develop a new handicapping system for women.

In one account, Hale described a pivotal moment early in her career when she gained acceptance for her skill on the field.

She had been hired by Heguy, a brilliant 10-goal player, to join his team for a tournament. But Heguy had neglected to tell his boss, the team’s sponsor: Henryk Richard de Kwiatkowski, the multimillionaire owner of the Kentucky thoroughbred breeding and racing stables Calumet Farm.

De Kwiatkowski rolled up to the field just before the first match of the tournament and spotted Hale on the sidelines.

“ ’This must be a girl from last night,’ “ Hale recalled him saying. “I’ve seen the look on his face. I’ve dealt with this look my entire career. No, I’m not the one that went and partied with them. I’m not the one that drinks with them. I’m not their best friend. I just want to play polo with them.”

De Kwiatkowski continued to scowl at Hale, and she noticed the Heguy did not say a word. Hale realized that Heguy had purposefully not told de Kwiatkowski about the new female player, knowing that the team owner would ultimately have no choice in the matter because the match was about to start.

They won the tournament.

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