In her first look at the national pastime, the queen met the players before the game and then took a seat in an upper-deck box enclosed in bulletproof glass. The queen, along with the President and Barbara Bush and Prince Philip, departed after watching two innings, during which there were no hits.
After arriving aboard the presidential helicopter, the two couples went to the Orioles dugout to meet the members of both teams. While Van Morrison's ''Brown-Eyed Girl" played on stadium loudspeakers, the visitors stood on formally printed place cards that identified their places.
The queen kept a constant smile on her face as she shook hands with every player, coach, trainer and batboy - first the Athletics and then the Orioles.
"He's the manager of the Orioles," Bush was heard to say as he introduced Frank Robinson. The manager later remarked: "It was very exciting. My heart's pounding. I'm not kidding. It was a very big thrill."
Baltimore second baseman Bill Ripken said of his fleeting brush with royalty, "I just said, 'Nice to meet you.' "
He had a slightly more in-depth discussion with Bush. "I told George he's doing a hell of a good job," Ripken said, giving a thumbs-up.
Even the garrulous Jose Canseco professed to be nearly speechless. The provocative Oakland outfielder said through a spokesman: "It was very exciting. I got to meet the queen and the President, but I didn't know what to say. We were rushed through."
Of all the players and coaches, only Oakland's Reggie Jackson took off his hat.
He later was asked why he had taken off his hat. Jackson, a coach with the team, said: "She's a lady. A lady of the world." He said that he had told her, "It's nice to meet you, your royal highness."
After the handshakes, the queen and the President stepped out onto the field and received a roar of applause from the 32,000 spectators.
Once the President and his guests were in their seats, Bush was seen gesturing toward the diamond and pointing, apparently explaining the game to her. She nodded in response.
A reporter who visited the box briefly said the queen removed her black gloves and placed them in front of her once she sat down. As the game began, Bush said: "Oh, here we go."
The President settled down to watch the game intently, munching on peanuts and sipping a soft drink. The queen alternately watched the action on the field and chatted with Barbara Bush.
When fans at one point booed an umpire's call, the queen looked perplexed. Barbara Bush appeared to explain what the sound meant.
The game capped the second day of the queen's third state visit to the United States, a day that took her from one of Washington's grittiest neighborhoods to two glittering receptions with Hollywood celebrities and political stars.
"I told the queen this was my palace," Alice Frazier, a 67-year-old resident of southeast Washington, said of the neat three-bedroom house she owns through a public-housing program. Frazier reached and gave the queen a hug, a breach of protocol. The queen froze and leaned away.
U.S. officials said the British government wanted to emulate the pilot American programs of converting rental tenants in the projects to prideful homeowners. The queen also dropped by an inner-city community center that aims to use sports to divert young people away from crime and drugs.