The Washington Nationals completed one of the most shocking championship runs in Major League Baseball history Wednesday by defeating Houston 6-2 to capture the US capital's first World Series title since 1924.

Howie Kendrick and Anthony Rendon blasted home runs and the Nationals rallied from two runs down after six innnings in the winner-take-all showdown to claim the best-of-seven final 4-3.

It was the first seven-game playoff series in North American sports where road teams won every contest.

The Nationals won the first crown in the club's half-century history, which began as the Montreal Expos and saw a move to Washington for the 2005 season.

The only other World Series win by a Washington team came 95 years ago when the Senators won a seventh-game thriller. The US capital has seen two clubs move away and went 33 years without a team.

The Astros won an MLB-best 107 games and were heavy favorites over a Nationals team that had only made the playoffs in the last days of the season and had never won a playoff series.

Instead, the World Series turned into a classic with an electric atmosphere and plenty of drama and the Nats went 5-0 in playoff elimination games to deny Houston a second title in three seasons.

"I've got a group of heartbroken men in there who did everything they could to bring a championship to this city and fell one win shy," Astros manager A.J. Hinch said.

Washington had trailed in all five elimination games before rallying to win and the clincher proved sweetest of all.

Astros starting pitcher Zack Greinke mystified the Nationals for 6 1/3 innings, allowing only one hit while Yuli Gurriel hit a solo homer and scored on a Carlos Correa single to give Houston a 2-0 lead.

Houston native Rendon, however, smashed a solo homer over the left-field wall off a Greinke changeup in the seventh, sending him to the showers after walking Juan Soto.

Kendrick followed by smacking a fastball from Astros reliever Will Harris off the right-field foul pole for a two-run homer that put the Nats ahead to stay.

The Washington Nationals celebrated Wednesday after defeating Houston 6-2 to win the World Series in a dramatic seventh game
The Washington Nationals celebrated after defeating Houston 6-2 to win the 2019 World Series in a dramatic seventh game. GETTY IMAGES NORTH AMERICA / Bob Levey

Washington added an insurance run in the eighth when Adam Eaton walked, stole second and scored on a Soto single.

In the ninth, Eaton singled with the bases loaded to drive in two more runs and all-but seal Houston's fate.

Patrick Corbin threw three shutout innings and allowed only two hits in relief of Max Scherzer and Daniel Hudson down the Astros in order in the ninth to complete the victory.

When the final moment came, the Nationals celebrated on the field, racing out of the dugout for an embrace after a historic triumph.

The Nationals, who were written off by many in May after a 19-31 start, joined the 1914 Boston Braves as the only World Series champions who were 12 games below .500 during the regular season.

Party in Washington

In Washington, hundreds of supporters shared the excitement, celebrating at a huge outdoor viewing party near the Nationals ballpark.

Nats fans made their trademark "Baby Shark" clap motion ahead of the final out, which set off screaming, yelling, tearful hugs and joyful dancing.

"How do you think I feel right now? We just won the World Series," said James Forrest, 32, waving a Nats flag.

The first World Series game seven with two Cy Young Award-winning starters, Greinke and Scherzer, was a pitchers' duel early.

Scherzer, who missed a planned game-five start with neck spasms, surrendered two runs on seven hits and three walks over five innings.

The Astros, however, stranded nine base runners during Scherzer's stay, squandering key opportunities.

"We had our opportunities," Hinch said. "The Nationals are really good."

Greinke, who hasn't won a playoff game since 2015, was obtained from Arizona at the July trade deadline. He fielded five outs, the most by a World Series pitcher since 1996.