"They'll still yell at me when a 3-2 slider doesn't break their way," he told The Associated Press. "But they'll be yelling at me because they didn't like my call, not because I'm a gay umpire."
Two weeks after Jason Collins retired as the NBA's first openly gay player, Scott added his name Tuesday to a growing list of gay and lesbian sports figures taking similar public steps. St. Louis Rams draft pick Michael Sam, NBA official Violet Palmer and WNBA star Brittney Griner are among those who have come out in recent years.
Scott didn't want to make a huge announcement heading into his 30th big league season.
The trade magazine Referee did a profile on the veteran crew chief in October, and didn't mention his sexuality. But the 55-year-old Scott wanted to share an important part of his life, and made the choice to include a picture of himself with partner Michael Rausch. They've been together for nearly three decades and married in November 2013 in Palm Springs, California.
The caption in Referee said: "He and his longtime companion, Michael Rausch, travelled to Australia for the 2014 season opener between the Diamondbacks and Dodgers."
The website Outsports.com later interviewed Scott and posted its story Tuesday.
"It's not like this was a secret. Major League Baseball knew my situation and it hasn't had any effect on my career. Zero bearing," Scott told the AP. "My fellow umpires have known for a long time."
"When I was home or out socially, I was gay," he said. "In my professional life, I wasn't. At least, not officially."
Baseball Commissioner Bud Selig praised Scott.
"To his friends and colleagues throughout the game, Dale is universally regarded as a class act," he said in a statement. "All of us at Major League Baseball are very proud of him, just as we have always been."
Scott has been an MLB umpire since 1986. He worked the World Series in 1998, 2001 and 2004, has called three All-Star games and plenty of playoff matchups, including the NL series between St. Louis and the Dodgers in October.
"He's an excellent crew chief and umpire," MLB umpire Dan Iassogna, who just finished his eighth season working with Scott, told the AP.
"But above all, he's been a true friend to my family and me. I've always been proud to walk with him, but never more proud than today," he said.
No big league player or manager has been openly gay during their active career. Glenn Burke and Billy Bean are among the players who later said they were gay, as did umpire Dave Pallone. At the All-Star break last summer, MLB hired Bean as a consultant to help the game achieve greater awareness and equality for the gay, lesbian, bisexual and transgender community.
Scott said he understood coming out "might open a Pandora's box" when he takes the field next year.
"We'll see when the season starts if this is still an issue," he said. "I suspect no."
In the immediate aftermath of the story becoming public, Scott said his cellphone and email "blew up" with messages.
"They all were all positive, except for one. I know that's going to happen, I understand it," he said.
Scott met Rausch, an artist, after the 1986 season at a bar in Portland, Oregon. The two now split time between Portland and Palm Springs. When they married, the mayor of Palm Springs officiated the ceremony.
Rausch is listed as Scott's domestic partner with MLB. The latest contract between the umpires' union and MLB took effect in 2010 and permitted umps to include domestic partners to allow them to receive benefits.
Scott said only once in his career has a player asked if he was gay, and that was through a mutual acquaintance, who brushed off the question.
"I'm not saying there aren't players on teams who haven't heard things or might've had an idea," he said. "But no one's ever brought it up to me, or said anything about it to me while yelling at me for calling strike three."