The Astros are going to the World Series for a number of reasons.

Saturday night marked the culmination of a lengthy, creative, bottoming-out rebuild gone right, a rebuild so extreme it had earned the club the “Disastros” moniker. No one is laughing now.

The Astros are going to the World Series because of the accumulation of hirings, signings, draft decisions, development and strategies executed well. Not everything went perfectly, but this is a game of probabilities, not certainties, and a lot of things went right.

That’s the big picture view. The smaller-sample truth is they needed a Game 7 to win Saturday night to have such a happy narrative be written, to advance to a second World Series appearances in franchise history. The Astros needed to match the moment and they did.

The Brian McCann trade was a big deal on Saturday for his deft catch of an accurate and gusty Alex Bregman throw home to cut down Gregory Bird in the fifth. The play kept the score a 1-0 Astros’ advantage. In the bottom half of the inning, McCann later added a two-run double to extend the lead to 4-0.

Game 7 starter Charlie Morton was signed by Houston to a two-year, $14 million deal in the offseason after a roller-coaster of a career. The deal struck some as curious given Morton’s spotty health and performance history. But Morton was a buy-low speculation add that has produced plenty of value. The Astros saw that Morton’s stuff had played up in 2016 when Morton simply decided to try to throw harder and miss more bats, and Morton’s stuff had never been better in 2017. It was rarely as good as it was Saturday night.

Morton, who has struggled mightily throughout his career when facing an opposing lineup for a third time, was not permitted to face the Yankees’ lineup for a third go-around despite five shutout innings Saturday. Morton essentially became the 1A portion of a tandem start with Lance McCullers as the 1B pairing. The Astros have been most aggressive organization in regard to tandem starts in the minors. This strategy alone is something of a victory for the sabermetric community. And as Dave wrote leading into the game, A.J. Hinch appeared to be losing faith in his bullpen. So Plan A was for McCullers to be the bullpen.

Morton handed the ball over to McCullers, who recorded his first save with four dominant innings. But it was an unusual outing, even for McCullers.

Major league baseball is in an age of extremes, from HR/FB and strikeouts rates, to velocity and injury trends. It’s also in an age of extreme breaking ball usage. Pitchers like Rich Hill and McCullers have questioned the necessity of having their fastball be a primary pitch. Among pitchers who threw at least 100 innings this season, McCullers led the sport in curveball usage (47.2%), and Hill was a distant second at 39.8%. (Hill’s curveball was less effective this year which likely explains the decline).

McCullers has been part of the wave pushing the game to new frontiers, questioning everything, but even he had never been as extreme as he was Saturday night. McCullers threw 54 pitches, striking out six and allowing just one hit. Of those 54 pitches, 41 were curves, a 75% rate. His previous career high for curveball usage in an appearance was on April 4 when when 68.9 percent of his pitches were curves.

How good was the pitch? FS1 commentator John Smoltz joked McCann didn’t even need signs behind the plate. The Yankees knew what was coming and it didn’t much matter. McCullers finished the game with 28 consecutive curves.

The following is a brief sampling of the quality of the pitch:

Starlin Castro has no chance in 7th …

Nor did Chase Headley …

or Aaron Judge in the eighth …

McCullers entered the game as something of an experiment. He was an over-slot signing in the Carlos Correa draft as the Astros tried to manipulate the new draft spending caps. He is extreme in regard to pitch usage. And now he tandem-ed a team into the World Series.

He was old school in his desire for the ball. Said McCullers to Ken Rosenthal on live television after the game:

“I told A.J. (Hinch) after we lost Game 4, ‘I don’t care what (my role) it is, I want the fu … I want the ball in Game 7’,” said McCullers, catching himself before using an expletive descriptor. “‘I will start the game. If you only want me to go three innings, I will go three innings. If you want me to come out of the ‘pen, I will come out of the ‘pen.’

“I told Dallas (Keuchel) that if I have the opportunity to end the game, I am going to empty the gas tank.”

And he did if he was drawing from a reservoir of curveballs.

The pitch was excellent in drawing 10 swinging strikes, five called strikes, and the average exit velocity of the six curveballs put in play was 79.2 mph.

It was McCullers out there to finish the game, but in a very unconventional, a very Astros Way: as a tandem starter, with a primary pitch as a curveball, a former over-slot draft pick who was part of one of the more creative and dramatic rebuilds in MLB history. And if it was not already, the journey can be considered a success for the team, for the individual, for a city that so desperately needs something to cheer for.

“This city, they deserve this,” McCullers said.

For Houston, for the Astros, McCullers authored a perfect ending to American League play. Now, a final chapter, and the Dodgers, await.