The Washington Nationals took home the 2019 World Series title in seven games on Wednesday, and while the 2020 MLB season is still five months away, odds for next fall's World Series and pennant championships are out. The latest 2020 World Series odds have this year's runner-up Houston Astros as 4-to-1 favorites to win it all, with the Los Angeles Dodgers and New York Yankees behind Houston with 5-to-1 odds. Eight (Astros, Dodgers, Yankees, Braves, Red Sox, Nationals, Indians and Cardinals) of baseball's 30 teams have World Series odds of 18-to-1 or lower. 

For the AL pennant, the Astros are a +225 favorite with the Yankees at +250. Over in the NL, the pennant favorites are the Dodgers with +250 odds and the Braves next on the board at +450.

The Astros were one game away from winning their second World Series title in three years, before the Nationals won two straight games in Houston to clinch the 2019 title. The club is expected to return the majority of their potent lineup in 2020, and they'll once again be the team to beat in the 2020 season. Gerrit Cole will be a free agent at the conclusion of the 2019 season, and even if he departs, Houston will be bringing back Justin Verlander and Zack Greinke to lead the pitching staff.

After back-to-back runner-up finishes in the World Series, the Dodgers were stunned by the World Series champion Washington Nationals in Game 5 of the 2019 NLDS. Starters Hyun-Jin Ryu and Rich Hill will be free agents ahead of 2020, but otherwise, L.A. should look to roll out a similar lineup next season.

The Nationals were +195 underdogs to the Astros in this year's Fall Classic. Houston was the biggest World Series favorite since 2007, and with Washington's win, it's the largest World Series upset since the Cincinnati Reds defeated the Oakland Athletics in a four-game sweep at +260 underdogs in the 1990 World Series.

Here are the Westgate odds (as of Oct. 31) to win the 2020 World Series and both pennants.

2020 AL pennant odds

Houston Astros9/4
New York Yankees5/2
Boston Red Sox5/1
Cleveland Indians7/1
Tampa Bay Rays10/1
Minnesota Twins10/1
Oakland Athletics15/1
Los Angeles Angels25/1
Chicago White Sox30/1
Toronto Blue Jays 40/1
Texas Rangers50/1
Seattle Mariners150/1
Baltimore Orioles500/1
Detroit Tigers500/1
Kansas City Royals500/1

NL pennant odds 

Los Angeles Dodgers5/2
Atlanta Braves9/2
Washington Nationals6/1
St. Louis Cardinals8/1
Philadelphia Phillies10/1
New York Mets10/1
Chicago Cubs10/1
Milwaukee Brewers10/1
Arizona Diamondbacks25/1
Cincinnati Reds25/1
San Diego Padres25/1
Colorado Rockies50/1
San Francisco Giants50/1
Pittsburgh Pirates100/1
Miami Marlins500/1

World Series odds

Houston Astros5/1
Los Angeles Dodgers6/1
New York Yankees6/1
Atlanta Braves10/1
Boston Red Sox12/1
Washington Nationals14/1
Cleveland Indians16/1
St. Louis Cardinals18/1
Chicago Cubs20/1
Philadelphia Phillies20/1
Milwaukee Brewers20/1
New York Mets20/1
Tampa Bay Rays20/1
Minnesota Twins20/1
Oakland Athletics30/1
Arizona Diamondbacks50/1
Cincinnati Reds50/1
San Diego Padres50/1
Los Angeles Angels50/1
Chicago White Sox60/1
Toronto Blue Jays80/1
Colorado Rockies100/1
San Francisco Giants100/1
Texas Rangers100/1
Pittsburgh Pirates200/1
Seattle Mariners300/1
Miami Marlins1000/1
Baltimore Orioles1000/1
Detroit Tigers1000/1
Kansas City Royals1000/1