This is the first time in Major League Baseball history that the two teams will face off in the postseason.
This will also be the first one-game playoff for either team since the MLB introduced the Wild Card Game in 2012. Anything can happen in a winner-take-all showdown, so it will be critical to leave everything on the field.
As the Nationals and Brewers prepare for this do-or-die matchup, let's take a look at how their cities match up.
Washington, D.C. vs. Milwaukee, Wisc. Tale of the Tape
Metro population: 6,216,589 (WAS) | 1,572,245 (MIL)
Top tourist attractions: Washington Monument, Lincoln Memorial, Jefferson Memorial, The White House (WAS) | Harley Davidson Museum, Milwaukee Art Museum, North Point Lighthouse (MIL)
MLB postseason appearances: 6 (WAS) | 5 (MIL)
World Series appearances: 0 (WAS) | 1 (MIL)
World Series championships: 0 (WAS) | 0 (MIL)
Famous celebrities: Duke Ellington, Marvin Gaye, Dave Chappelle (WAS) | Gene Wilder, Dan Harmon, Les Paul (MIL)
Most popular sports team: Milwaukee Brewers (MIL) | Washington Redskins (WAS)
City's nickname: The DMV (WAS) | Cream City (MIL)
What the city is known for: Being the capital of the United States (WAS) | Brewing beer (MIL)
Television shows based there: Any show ever about politics (WAS) | Happy Days, Laverne and Shirley (MIL)
Cost of museums: Free (WAS) | Not free (MIL)
Famous bodies of water: Potomac River (WAS) | Lake Michigan (MIL)
MORE NATIONALS NEWS:
Regular season recap: How the Nats fared against the Brewers this year
Taking the Metro: WMATA encourages fans to use Metro
Nationals vs. Brewers: Washington or Milwaukee? A tale of the tape originally appeared on NBC Sports Washington