WASHINGTON -- Since baseball returned to Washington in 2005, there have been numerous ceremonies and parties to mark different milestones.

They were all just practice.

On Saturday night, residents of the nation's capital saw what they have waited so long for: baseball in a baseball stadium.

The Washington Nationals defeated the Baltimore Orioles, 3-0, in an exhibition game in front of about 25,000, almost all of whom were seeing Nationals Park for the first time.

After decades without a team and three more years of anticipation and construction, Mayor Adrian Fenty threw the ceremonial first pitch, a strike to Cristian Guzman. Fenty was followed by Jason Bergmann, who opened the game.

"It was definitely cool, but it only lasted for one pitch," Bergmann said. "Then it was down to business."

He conducted his business effectively, backed up by a Nationals offense that scored two runs in the first and added another in the fifth, all of them courtesy of walks and defensive mistakes by the Orioles.

The players weren't the only ones getting down to business, as team president Stan Kasten and stadium vendors prepared for the crowds. Kasten said that the food vendors referred to park visitors as "tourists," because everybody wanted to wander around and see everything.

"I can't imagine the concourses will be that crowded every night," Kasten said. "At some point, people are going to settle down and watch the game, I hope."

Though 34,635 free tickets were issued, only about 25,000 showed up, but it was enough to test every aspect of the park.

Only one concession stand had a long line: Ben's Chili Bowl, a D.C. favorite that until Saturday night had only ever operated out of one location -- on U Street, in the District. Customers who have been to the original Ben's would have felt right at home, as long lines are the norm there as well.

But once the fans had done their touring, the focus shifted back to baseball, and Nationals Park is a good place to watch it. It's been 47 years since Griffith Stadium hosted its last game, making two full generations of Washingtonians that saw their first game in a local baseball stadium on Saturday.

It's fitting that they saw their team play the Baltimore Orioles, the club that served as the city's surrogate all that time. But it appears that the city is ready to say farewell to its neighbors up north -- the few fans who shouted for the O's during the national anthem were booed down.

The Orioles themselves didn't fare much better in the game. Bergmann pitched five innings of shutout baseball, allowing just one hit.

The offense backed him up, with Guzman walking to open up the first, Lastings Milledge being hit by a pitch and Nick Johnson recording the game's first hit, an RBI single. Austin Kearns hit a double to bring in Milledge.

In the fifth, the team again rallied, with Ryan Zimmerman walking, Johnson reaching on an outfield fielding error and Kearns walking. Paul Lo Duca walked with the bases loaded to make the score 3-0.

The only offense the Orioles could get going was from Nick Markakis, who walked twice and stole two bases.

A majority of the crowd stayed through the seventh-inning stretch despite the cold temperatures.

Bergmann said that the cold, combined with the exhibition nature of the game, may have caused players to hold back. Ronnie Belliard added that because of that, it's tough to read how the park will play.

"We just have to wait for the sun to come back out and see what happens," Belliard said.

The team has already discovered some unintentional -- or perhaps not -- home-field advantages. Though the Nationals dugout and clubhouse are on the same level, visiting teams have to climb a couple dozen stairs to get to theirs.

Manager Manny Acta spent the game in his traditional perch, in the corner of the dugout, and offered rave reviews of the stadium. But he said that Saturday's game was mostly about the fans, as well as the dozens of local dignitaries who helped make the stadium happen and who were honored before the game.

"This isn't just about us," Acta said.

Saturday was about the fans, who enjoyed an atmosphere they hadn't since 1961. They're ready for the season, and the players know those fans are ready for a winner.

"It's the nicest stadium I've ever been to, and we're lucky to have it," Zimmerman said. "But now we just want to win."