Baseball made a winning return to Washington as new DC team the Nationals beat Arizona 5-3 on their home debut.
US President George W Bush threw out the ceremonial opening pitch of the National League encounter.
Livan Hernandez shone for the Nats, pitching eight and a third sparkling innings, giving up just one hit.
Vinny Castilla drove in four runs for the hosts, and closer Chad Cordero took over from Hernandez in the ninth to claim his second save of the season.
The game took on a World Series atmosphere as fans welcomed back big-league baseball to Washington for the first time since the Senators packed up and left town for Texas in 1971.
Bush, wearing a red Nationals jacket, waved to the crowd after becoming the first president since Richard Nixon in 1969 to throw out the ceremonial opening pitch in Washington.
The tradition was started 95 years ago to the day by President William Howard Taft.
The Nationals, owned by Major League Baseball while bids are being solicited by groups to buy the club, were the Montreal Expos until the end of last season and played before sparse crowds at home.
A portion of their home schedule was moved to Puerto Rico because the crowds in Montreal were so small.