The St. Louis Cardinals celebrate their 13-1 win over the Atlanta Braves in game five of Major League Baseball's National League Division Series

Los Angeles (AFP) - The St. Louis Cardinals exploded for 10 runs in the biggest first inning in Major League Baseball playoff history on Wednesday, routing the Atlanta Braves 13-1 to reach the National League Championship Series.

Braves starting pitcher Mike Foltynewicz, who pitched seven scoreless innings in a game-two victory in the best-of-five division series, retired just one batter before he was pulled in the first frame.

Tommy Edman, Dexter Fowler and Kolten Wong each had two-run doubles, Cardinals pitcher Jack Flaherty walked with the bases loaded to force in a run, and St. Louis scored their final run of the first on a strikeout when Braves catcher Brian McCann couldn’t corral a pitch in the dirt.

St. Louis sent 14 batters to the plate before Braves relief pitcher Max Fried finally ended the inning.

The Cardinals’ 10 runs were the most ever in the first inning of a post-season game and tied for the most runs in any inning of a playoff game.

“I don’t know that I’ve seen that many guys hit in the first inning that quick in my entire life,” said shellshocked Braves manager Brian Snitker. “I don’t know. It wasn’t how we drew it up, I know that.

“I don’t know,” he said again. “That thing just kept rolling and we couldn’t stop it.”

The Cardinals’ 13 total runs matched their total in the first four games of the best-of-five NL Division Series.

The Braves endured their 10th straight playoff series defeat while the Cardinals wrapped up a 3-2 series win to reach the NLCS for the first time since 2014.

St. Louis will face either the Los Angeles Dodgers or Washington Nationals for a place in the World Series.

“We know we can beat anyone at this point,” Wong said.

The Dodgers, trying to get back to the World Series for a third straight year, hosted the Nats in game five of their series later Wednesday.