EMERYVILLE, Calif. — Glenn Burke was 27 when he walked out on Major League Baseball, his promising career as an outfielder undone mostly by the burden of being a partly closeted gay man.

It was 1980, and it was more important, Burke later explained, to be himself than to be a professional baseball player.

“It’s harder to be gay in sports than anywhere else, except maybe president,” Burke said in 1982, when he came out publicly in an Inside Sports magazine story. “Baseball is probably the hardest sport of all.”

More than 30 years later, and nearly 20 years after Burke’s death, no active MLB player yet has publicly disclosed that he is gay.

There likely are dozens of gay men currently playing, but the sport awaits its Robbie Rogers (soccer), its Jason Collins (basketball), its Michael Sam (football).

In the meantime, Major League Baseball is trying to ease the way for those surely to come. As part of a concerted effort to demonstrate an atmosphere of tolerance and inclusion, the league invited Burke’s family to Tuesday’s All-Star Game in Minneapolis — its first official recognition of Burke’s early role in a movement just now gaining traction across the sports landscape.

“He was a pioneer, and should be recognized,” MLB spokesman Pat Courtney said.

In attendance Tuesday night was Lutha Burke, one of Glenn Burke’s five surviving siblings, who cared for Burke in his final months as he withered and died from the effects of AIDS, and her daughter Alice Rose. Burke died in 1995.

“It was overdue, and Glenn has a story that needs to be told,” Lutha Burke, 66, said over a cup of coffee, sitting beside Rose. “Glenn wouldn’t be upset that it took this long. He’d just say, ‘It’s about time you guys showed up.’”

In addition to attending the All-Star Game and its surrounding festivities, Lutha Burke and Rose attended a news conference with Commissioner Bud Selig.

The league announced that Billy Bean, who played six seasons in the majors and came out publicly in 1999, four years after he retired, will work with the league on its inclusion efforts.

Bean followed a path first walked in baseball by Glenn Burke. Raised in Oakland and a star athlete at Berkeley High School, Burke was drafted by the Dodgers in 1972 in the 17th round. After a few seasons in the minor leagues — a time when Burke came to realize that he was gay — he made his debut with the Dodgers in 1976 at age 23.

With his combination of strength and speed, Burke was compared by one coach to Willie Mays. He might have been more like Rickey Henderson, also raised in Oakland, whose Hall of Fame career began with the A’s in 1979.

But Burke’s major league career lasted only 225 games, smattered across four seasons. He appeared in more than half of the Dodgers’ games in 1977, when they reached the World Series, mostly as a defensive replacement and pinch hitter. He started Games 1 and 4 of the National League Championship Series against Philadelphia, and Game 1 of the World Series against the New York Yankees.

Few knew he was gay, but rumors percolated. Burke was wildly popular in the clubhouse, known for playing loud music, dancing and spot-on imitations of comedian Richard Pryor. He is widely credited for inventing the high-five.

The Dodgers were less enamored. Burke had a strained relationship with manager Tommy Lasorda, whose son, Tom Lasorda Jr., befriended Burke. (The younger Lasorda died in 1991 of complications from AIDS, though his father routinely cited other illnesses, from pneumonia to cancer, and denied that his son was gay.)

Al Campanis, the Dodgers’ vice president, offered Burke bonus money if he married, something he later said was not a bribe but a gesture rooted in tradition, as the Dodgers encouraged family stability and maturity on their roster.

In May 1978, just as teammates began realizing that Burke was gay, he was traded to the A’s for the veteran Bill North. It was not a popular move in the clubhouse.

“He was the life of the team, on the buses, in the clubhouse, everywhere,” Davey Lopes, a teammate, said of Burke the day after the trade. When Burke came out in 1982, Lopes was among several former teammates who said that Burke was traded because he was gay.

Back home in Oakland, Burke increasingly spent time across the Bay Bridge, in San Francisco’s Castro district, the heart of gay culture. Suspicions about his sexuality swirled. A friend tried to steer him and his story to San Francisco Chronicle columnist Herb Caen, but Burke declined. Caen wrote only that a local ballplayer could be found on Castro Street.

Burke started regularly in the outfield for the A’s in 1978, but a pinched nerve in his neck in the 1979 season kept him off the field. He refused to take cortisone shots to get back on the field and simply left the team. He was 26.

“I probably wouldn’t have left if there hadn’t been the other problem, the gay thing,” Burke said in the 1982 Inside Sports story. “But put it all together, and it was too much.”

By 1994, he was diagnosed with AIDS. Lutha Burke searched for him on the streets of San Francisco and brought him home to Oakland, knowing he would die.

“All I do is lie in bed and cry and holler for Lutha,” he told The New York Times. He died at age 42.

For nearly 20 years, the Burke family heard nothing from Major League Baseball (though the A’s, Lutha Burke said, were always supportive, helping raise money during Burke’s illness). That changed recently, when Alice Rose received a call that she relayed to her mother. Baseball wanted to recognize Burke’s contribution to the sport.

“I had to get off the phone and catch my breath,” Lutha Burke said. “I called back and told her: ‘That’s wonderful. It’s time.’ ”