PITTSBURGH — Brandon Crawford figured the San Francisco Giants needed one run, maybe two, the way ace Madison Bumgarner was dealing.

A grand slam provided all that and more, silencing a revved-up crowd and propelling San Francisco into the meat of the playoffs. Streaking in May and slumping in September, the Giants are back to their old resilient selves in October.

Hey, it’s what they do this time of year.

Crawford’s slam off Edinson Volquez in the fourth inning led the Giants to an 8-0 victory over the Pittsburgh Pirates in the National League wild-card game Wednesday night, sending San Francisco on to Washington for the best-of-five Division Series starting Friday.

“We thrive in these situations,” Crawford said. “I don’t know what it is. We just keep fighting no matter what the circumstance.”

The Giants won their eighth consecutive postseason game and seventh straight with their season on the line, a streak that dates back to their run to a World Series title in 2012. While much work remains before they can start thinking about the franchise’s eighth championship, there was certainly a familiar feeling at PNC Park as San Francisco dismantled the Pirates.

“We’ve been through it before, a lot of this team has,” Brandon Belt said. “We used that experience tonight. We know when we get in these situations we’re going to have a good ballclub.”

Particularly when Bumgarner is on the mound. He tossed a four-hitter with 10 strikeouts, needing 109 pitches to put a quick end to Pittsburgh’s second straight playoff appearance.

Mixing his fastball with a slider and curve the Pirates rarely touched, Bumgarner was in complete control and looked very much like the ace who won 18 games during San Francisco’s bumpy regular season.

“If you don’t want to pitch in these games, you probably need to find something else to do,” he said.

No chance of that for Bumgarner or the rest of a roster that flourishes once the calendar flips past September. Crawford’s grand slam was the first in postseason history by a shortstop — and he wasn’t aiming for the fences.

With the bases loaded in the fourth and nobody out in a scoreless game, Crawford turned on Volquez’s hanging breaking ball and sent it to right. Pittsburgh’s Travis Snider waited to play it off the wall. He never got the chance, instead slumping his shoulders as the ball landed a couple of rows deep to give the Giants a 4-0 lead that felt considerably larger.

“I was in shock a little bit,” Crawford said.

So were the Pirates, who never recovered. One night after Kansas City edged Oakland in a thrilling start to baseball’s postseason, this one was over by the middle innings.

Overpowering one of the NL’s best lineups, Bumgarner walked one and threw 79 strikes in his latest stellar October performance. The big left-hander, who allowed only four singles, has thrown 15 scoreless innings in two World Series starts.

“We got outplayed tonight,” Pittsburgh second baseman Neil Walker said. “Bumgarner went out there, he did what he wanted to do. He put up the strike zone and he made it tough on us.”

Belt drove in three runs as the Giants padded the lead late. By then the black-clad crowd that began the night in a frenzy was watching in dismayed silence.

“We’ve been there before,” Belt said. “It’s a lot of fun when you’re on the road. … You know you’re doing something good when the crowd goes silent.”

Volquez was trying to cap his comeback season by sending Pittsburgh to the NLDS for the second straight year, but he couldn’t match Bumgarner.

The right-hander cruised until the fourth, when a pair of singles and a walk loaded the bases with none out. He’d retired Crawford 19 of the 22 times he’d faced him during his career.

It’s the 24th that he’ll remember.

“I tried to bounce it down, back foot, and the ball just kept going,” Volquez said. “Bad spot.”

That was more than enough for Bumgarner. Pittsburgh, fourth in the majors in extra-base hits this season, rarely hit the ball hard.

Bumgarner was helped by his defense, too. Third baseman Pablo Sandoval — all 245 pounds of him — flipped over the railing in front of the Pittsburgh dugout to track down a foul popup off the bat of Russell Martin.

Sandoval landed on his feet, a perfect symbol of San Francisco’s seemingly endless resiliency when October rolls around.

Back in the playoffs after winning the World Series in 2010 and 2012, the Giants are looking to continue their every-other-year success.

Pittsburgh, on the other hand, was unable to duplicate last year’s victory over Cincinnati in the wild-card game that followed a 21-year playoff drought. Playing before raucous crowds at PNC Park, the Pirates pushed St. Louis to a decisive Game 5 before losing their NLDS.

This year, Pittsburgh went 17-9 in September while taking the Cardinals to the final day of the season in an attempt to win the NL Central.

There will be no extended playoff stay this time after Crawford’s grand slam, the fourth in Giants postseason history.

Shortstop had been the only position — including pitcher — without a slam in postseason play.

“That’s crazy,” Crawford said. “With all the great shortstops that have played before, that’s pretty special. I’m happy to be able to do it.”

TRAINER’S ROOM

Giants: OF Michael Morse was left off the wild-card roster while he recovers from a strained oblique that has sidelined him since Sept. 20. Manager Bruce Bochy said the veteran would be activated “at some point” in the next round.

UP NEXT

It’s on to Washington for the Giants, where they will face rookie manager Matt Williams and the Nationals. Williams was once a star third baseman for San Francisco.

The Giants went 2-5 against Washington this season, getting outscored 41-30.