(CNN) -- Jackie Robinson would be proud.
Chicago's Little League team named for the baseball icon -- who broke his sport's color line -- is headed to the Little League World Series championship, after topping Las Vegas in the U.S. title game on Saturday.
The Jackie Robinson West squad -- which is composed entirely of young African-Americans -- will square off with the tournament's international champions from Seoul, South Korea, in Sunday's final.
The South Koreans advanced after crushing Japan 12-3 earlier Saturday.
Chicago entered its own contest Saturday as the underdog. Its foe, Las Vegas, had beaten every team it faced -- including Chicago, which it crushed by a 13-2 score.
But this time proved to be very different.
The two squads were tied 3-3 after the first inning, before the Jackie Robinson West entry jumped ahead by one run the next inning.
Las Vegas took the lead in the fifth on a two-run home run by Brad Stone, only to have Chicago answer with three runs of its own.
Ed Howard moved from his usual perch at shortstop to pitcher in the sixth and final inning and -- with a game-ending double play -- sealed Chicago's 7-5 win.
That victory set off jubilant celebrations at the game in Williamsport, Pennsylvania, as well as Chicago, including among locals who cheered after watching the final outs at a Cubs game at Wrigley Field.
Chicago Mayor Rahm Emanuel credited "their positive attitude and success on the field (for rallying) people from every neighborhood."
The boys from Chicago's South Side also got hearty congratulations from outside the Windy City, including ex-Chicago White Sox great and baseball Hall of Famer Frank Thomas and longtime President Barack Obama adviser David Axelrod.
"Congrats to the Chicago Little Leaguers on winning the US title!," tweeted Steve Kerr, a former standout with the NBA's Chicago Bulls and now coach of the Golden State Warriors. "So inspiring to see the poise and skill at such young ages. Awesome."