WASHINGTON -- This was it. This was the moment.

The Nationals needed one big hit in the sixth inning to change everything Saturday night in an 8-1 loss to the Astros in Game 4 of the World Series. But the big hit never came, and quickly everything took a turn for the worse. The lack of an offensive eruption in the sixth affected how the Nats used their bullpen in the seventh, which is how a three-run deficit became a seven-run loss to even the best-of-seven series.

Houston carried a 4-0 lead into the bottom of the sixth when right-hander Josh James walked Gerardo Parra and Adam Eaton to put runners on first and second with one out. Will Harris entered the game to face Anthony Rendon, who reached on an infield single to load the bases. A run scored when Juan Soto grounded out to first base for the second out. Howie Kendrick struck out swinging to end the inning as the Nationals finished the game 1-for-9 with runners in scoring position. They are 1-for-19 with RISP in the past two games.

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“Hitting in general is, I think, pretty tough,” Trea Turner said. “It's a failure sport. I don’t think it’s a matter of us having bad at-bats or whatever it may be. I think we've got runners on base, we've had the at-bats, we just haven't got the big hits.”

Kendrick was more succinct.

“What are you going to change?” asked the National League Championship Series MVP. “It’s not like guys are going up trying to strike out.”

But if the Nats scored a few more runs in the sixth to move within a run or even tie the game, manager Dave Martinez would have used his bullpen differently in the seventh, meaning Daniel Hudson or Sean Doolittle would have pitched.

“Yeah, it definitely would have been different,” Martinez said.

Tanner Rainey started the seventh inning instead. He walked Kyle Tucker and George Springer before he got José Altuve to fly out for the first out. Martinez summoned Fernando Rodney from the bullpen, but he allowed a single to Michael Brantley to load the bases. Alex Bregman then crushed an 0-1 sinker from Rodney for a back-breaking grand slam, the 20th grand slam in World Series history.

“I made a mistake and I paid,” Rodney said.

Bregman got to see Rodney on back-to-back days, facing him in the sixth inning Friday night in Game 3. He wasn’t sure if it helped him. It certainly didn’t hurt.

Martinez said he had no regrets, even as he acknowledged that with a smaller deficit, he might have proceeded differently.

Asked why he wouldn’t just use Hudson in the seventh to keep the game close, Martinez said, “You don’t chase wins. Come tomorrow, we’re up 2-0 and all of a sudden we’re in the seventh inning, you have to use Hudson for two innings, you have to use Doolittle for two innings. You want those guys ready to pitch. I know we got a day off the next day. All this was talked about before the game. But you’re down still three runs, and like I said, Rainey has done well for us. It just happens he couldn’t throw strikes tonight.”