WASHINGTON -- Astros manager AJ Hinch leaned heavily on his relief corps to take care of business in Game 3 on Friday night at Nationals Park, all but emptying his bullpen to secure Houston’s 4-1 win over the Nationals and avoid what would’ve been a historically insurmountable hole in this best-of-seven series. The Astros will need even more of the same from their relievers to guarantee the World Series goes back to Minute Maid Park.

“Every World Series game is a bullpen game, mostly,” Hinch said afterwards. “At some point.”

For a series where the storylines have hinged on starting pitching thus far, that point came when Hinch replaced Zack Greinke with Josh James in Friday’s fifth inning with two on and two out and the Astros cradling a two-run lead at the time. The ripple effect of that decision now shapes this second leg of the series, no matter how far it goes.

“That moment felt like power and a new look was going to be what we needed,” Hinch said. “Josh James came in and did his job.”

The immediate byproducts of Hinch’s hook: James struck out Ryan Zimmerman to escape the jam, four other relievers logged four scoreless innings behind him, and Houston was provided the luxury of not having to turn to Gerrit Cole on short rest in a win-or-go-home situation on the road in Saturday night’s Game 4. Instead the American League champs will tab rookie righty Jose Urquidy as part of a bullpen game looking to tie the Fall Classic at two games apiece.

Signed by the Astros out of Mexico in 2015, Urquidy made his MLB debut on July 2 and started seven of his nine regular-season games this season. He posted a 3.95 ERA, including 4.24 as a starter, with his last appearance in that role coming on Sept. 27 against the Angels (six scoreless innings).

"Obviously very happy," the 24-year-old said of learning he would start Game 4. "Very few Mexicans have had this opportunity, and for me to be in this position, I'm obviously very happy about that and will try to take advantage of it as much as possible."

Hinch said it’ll be “all hands on deck” again behind Urquidy, knowing he’ll likely need to cover six innings with the ’pen even if Urquidy cruises. The rookie hasn’t been asked to throw more than 2 2/3 innings in either of his two postseason appearances and he last logged six innings on September 27, almost a month ago. This will be Urquidy's first postseason start.

“He can go as long as he's good,” Hinch said. “I don't have necessarily a predetermined plan on how many innings, how many pitches.”

Those looking for at least a loose blueprint might instinctively turn to AL Championship Series Game 6, when Houston deployed seven relievers to piece together its clincher against New York. Brad Peacock started that game opposite the Yankees' right-handed heavy lineup, followed by James, Ryan Pressly and eventually Urquidy, whose 2 2/3-inning outing was the longest of the night. Hinch then turned to Joe Smith, Will Harris and Roberto Osuna for the final outs.

But focusing on the second half of Friday’s win may serve as a better model. Hinch said the presence of left-handed-hitting Adam Eaton and Juan Soto atop the Nationals’ lineup factored into the decision to go with Urquidy, who posted reverse splits as a rookie. Lefties hit just .179 with a .530 OPS in 81 plate appearances against Urquidy, thanks in part to the changeup he throws twice as often to left-handers.

“It’s not just a one-size-fits-all strategy when you’re facing different teams,” Hinch said. “[The Nationals] offer something a little different than the previous decisions we’ve made when you just look at the balance they have at the top of their order.”

Another factor as to which reliever would start was the consideration of being in a National League park, and the strategy that comes with it.

"I can't be quite as quick with the pitching, given that you have to always be aware of where the at-bats are coming," said Hinch. "There are probably some relievers that hope I do so they get an at-bat in the World Series, but certainly I don't want to see it."

With essentially the season on the line Friday, Hinch stayed away from struggling righty Pressly and instead turned to James (one huge out), Peacock (one out), Harris (five outs), Smith (three outs) and Osuna (three outs). Smith, Harris and Osuna have all appeared in the Astros’ past five wins; at least one has pitched in each of Houston’s victories this October.

(The Astros’ two other active relievers, Héctor Rondón and Chris Devenski, present Hinch with lower-leverage options.)

The reason why is clear: Harris is unscored upon over 8 1/3 innings, having retired 25 of his 30 batters while striking out 10. Throw Smith in, and the pair has held opponents to one run over 15 2/3 innings. The rest of the ’pen owns a 4.28 postseason ERA, more than half a run higher than their 3.75 regular season ERA.

If Houston wins Game 4 by maxing out the 'pen -- while employing Smith, Harris and Osuna -- it will have been worth it, as the Astros will be guaranteed a Game 6 back home on Tuesday night.

But if they lose Game 4 while using one, two or all three of their back-end trio, that would leave them in a perilous position in a must-win Game 5, with each of those three looking at pitching on a third straight day.

Smith, who returned in mid-July from a torn Achilles suffered in 2018, did not pitch on three consecutive days this season. Harris did it just once, on April 27, allowing two runs on two hits while recording just one out in a 4-3 win over the Indians. Osuna, however, did it three times, pitching three perfect innings with four strikeouts.

For now, the spotlight is on Saturday’s pivotal game.

“We understood today we needed to play our best brand of baseball, and hopefully that was going to be good enough to get a win, and today it was,” Harris said. “And then tomorrow it's just a matter of doing that same thing. Every man in there was aware of where we were and understood that today was an important -- to do your job today as well as you could was very important.”