WASHINGTON -- For most of his life as a baseball fan -- from playing the game in his childhood to watching as a fan back when the Washington Senators were the team in D.C. to when he started as a U.S. Congressman in 1981 -- Barney Frank would have never imagined anything like Tuesday night at Nationals Park.

On the scoreboard inside the stadium, the team’s signature Curly W was painted in rainbow colors. The DC Different Drummers and Cheer DC performed as they welcomed fans entering the stadium via the Center Field Plaza. The Gay Men’s Chorus of Washington gathered on the field to sing the national anthem. The in-game marriage proposal shown on the scoreboard in between the sixth and seventh innings featured a man proposing to another man -- and the 32,573 fans in attendance stood for a round of applause when he said, "Yes."

And Frank and his husband, Jim Ready, stood together on the mound as Ready threw out the ceremonial first pitch on the 15th annual Night OUT at Nationals Park, one of the largest and longest running LGBTQ nights in professional sports. They followed it up with a kiss.

“When I was a kid playing baseball, being gay was the worst thing,” said Frank, the first member of Congress to come out voluntarily as openly gay. “Nobody ever wanted to say it or do it.”

The Nationals have been hosting this event since they moved to D.C. in 2005, and they have tried their best to continue to embrace their fans in the LGBTQ community. Fans who purchased a ticket to the event received a limited edition Night OUT T-shirt, and for each ticket, $5 was donated to Team DC’s scholarship fund. The Nats set up a “community village” at the ballpark, giving local non-profit programs supporting the LGBTQ community a chance to connect with fans during the game.

All efforts to make Nationals Park a more welcoming place for all fans.

“It’s great, we keep making progress,” Frank said. “And it’s a good sign, too, that we’re not just winning a narrow segment [of fans]. It’s broad acceptance.”

Behind the plate to catch the first pitch was Nats closer Sean Doolittle, who has been one of baseball's most vocal supporters of the LGBTQ community and Pride night. Doolittle and his wife, Eireann Dolan, have supported Pride night dating back to his time with the A’s, when they gathered enough money to purchase about 900 tickets after the first event in Oakland received public backlash.

So it was not a surprise to see Doolittle chatting and posing for photos pregame on the field with a number of different Nationals fans and guests, before showing off the Nationals Night OUT T-shirt with the rainbow-colored Curly W he was wearing under his uniform.