Two seasons after considering retirement, Aníbal Sánchez not only will be the starting pitcher in the first World Series game in Nationals Park. He might be the pitching difference in this World Series because he provides the Nationals with a dependable fourth starter the Houston Astros don’t have.

“Blessing,” Sanchez said of the chance to start Game 3 on Friday night. “I feel really, really [blessed].”

Sanchez has pitched well this postseason — five innings and one run against the Los Angeles Dodgers, a no-hitter into the eighth against the St. Louis Cardinals — but just as importantly, his reliability allowed Manager Dave Martinez to deploy third starter Patrick Corbin out of the bullpen in Game 1 while bumping his start from Game 3 to Game 4 to provide proper rest.

On the other side, Houston assembled a terrifying trio of starters this season — Gerrit Cole, Justin Verlander and Zack Greinke — but their fourth starter, veteran left-hander Wade Miley, did not make the World Series roster after they decided they’d prefer to cobble together innings from relievers in Game 4.

This divide stretches back to how the Nationals and Astros thought about roster-building last offseason. The Nationals signed Corbin for six years and $140 million to cement a Big Three with aces Max Scherzer and Stephen Strasburg, and then they prioritized adding a strong fourth starter. They traded away Tanner Roark and turned to free agency, signing Sanchez in December to a two-year, $19 million deal.

Sanchez is a kitchen-sink pitcher with two change-ups and multiple speeds on every pitch, and after getting released by Minnesota in March 2018, he had rebuilt his career in Atlanta with a 2.83 ERA over 24 starts.

Then, the Nationals also made a push for Miley. They offered a one-year deal in the range of $4 million, according to a person with knowledge of the discussions. But Miley wanted a longer contract so he signed with Houston, for two years and $6 million, and had a solid season that fell apart in September.

Miley mopped up in the ALDS and wasn’t on the roster in the American League Championship Series. José Urquidy has been average, and flashed potential, as a starter-reliever hybrid.

The bet on Sanchez looked riskier early this season. The right-hander lasted four innings and allowed four runs in his season debut against the Philadelphia Phillies, and by mid-May, he was 0-6 with an ERA over 5. He departed a start against the New York Mets after 1⅓ innings because of a left hamstring strain.

When Sanchez returned from the injured list, though, everything changed. He made his first start back against the juggernaut Atlanta Braves and allowed one hit and no runs over six innings. His resurgence coincided with the team’s in late May, and he stabilized the fourth slot in the rotation.

Martinez attributed the newfound success to refined mechanics. Sanchez used his legs more effectively. He threw with “conviction.” He stayed down in the zone. Sanchez thought “everything was the same” pitching-wise before and after the IL.

What Sanchez brought to the Nationals extended beyond a solid start every fifth day. When the team acquired Gerardo Parra in late May, when the veteran outfielder’s infectious energy began transforming the clubhouse culture, Sanchez became an eager co-conspirator. He stood in line with Parra for free sunglasses, and they’ve worn them in the dugout as good-luck charms all season. He started using the aux cord to blast Latin music in the clubhouse as often as possible, including slow Sunday mornings. He joined Parra in ritually hugging Strasburg in the dugout following Strasburg’s starts.

On Thursday night, Martinez praised what Sanchez has done this season and expressed confidence in the starter who seems to have more pitches every time he starts.

“It’s been huge,” Martinez said of the flexibility Sanchez affords. “Everybody talks about our Big Three, but Aníbal has pitched unbelievable. … He gives us a chance to win ballgames every outing.”

Staff writer Jesse Dougherty contributed reporting to this story.

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