Before a big, bouncy, blue Wrigley Field partied like it was 1945, before the Chicago Cubs thumped Clayton Kershaw and the Los Angeles Dodgers, 5-0, to win the National League pennant, there was a quiet moment that captured the high stakes, the strained nerves and the vulnerable pleading sense of “please, please . . . oh, please” that surrounded this Cubs team.

Twenty minutes before Game 6 of the NL Championship Series, Chicago’s Dexter Fowler — the man destined to be the ignition switch in a victory that will send the Cubs to their first World Series since World War II — walked alone to dead center field.

Fowler sought out the geometrical middle of the outfield wall, not the 400-foot sign that has always been slightly off-center. If you’re a Cub, you soon learn every iota of lore, every idiosyncrasy of this park, as well as all the curses and charms that it supposedly contains. You become a brick in that wall, a piece of this history with all its summer fun, its generations of memories and 108 years of autumn loss.

When Fowler reached the exact point he wanted, he leaned forward to place his head against the brick wall, sticking his head into the ancient Wrigley ivy, right up to his ears. He stayed there for many seconds, as if meditating, or invoking, or maybe just hoping that, finally, this would be the long-sought season, the one deferred for generations that now seems so close at hand. Then Fowler rubbed the wall vigorously with his hand, for luck, and ran back toward his teammates.

All this is fine and good, but what Fowler did to Clayton Kershaw, the greatest pitcher of this era, mattered far more. On the Los Angeles left-hander’s third pitch in the bottom of the first inning, Fowler executed the Cubs’ game plan perfectly — don’t try to pull Kershaw, just turn aside his wrath, twist his pitches to the opposite field.

Fowler’s line drive landed fair by a yard down the right field line and bounced into the roaring Wrigley stands for a ground-rule double. Kris Bryant’s sliced single in the same direction brought Fowler home. The ancient press box quivered and shook.

In games of this magnitude, and symbolism in the case of the Cubs, setting an early, nerve-untwisting tone can be vital. “Just be ourselves once again. Go out there and play the game freely,” Cubs Manager Joe Maddon had said before the game. “When you get to this particular moment, to try to avoid being outcome-biased, just . . . continue to work on the process, which is inning by inning — score first, win the inning. Those are the kind of thoughts that get you beyond this moment.”

Before that first inning was over, Bryant had also scored, for a 2-0 lead, thanks to a two-base outfield error by rookie Andrew Toles and a sacrifice fly by Ben Zobrist.

However, by the bottom of the second inning, Kershaw was about to squirm out of a two-out, man-on-second jam when he got ahead of Fowler 0-2. Then the Cubs and all of Wrigley Field found out the true state of Kershaw affairs. He laid a fastball down the middle that Fowler lashed to left for an RBI hit and a 3-0 lead.

The Cubs were on their way. At last, the late Harry Caray proved to be correct, but not just about one Chicago home run, but an entire Cubs season: “It might be. It could be. It is!”

Given that early lead, Kyle Hendricks, the Cubs elegantly subtle starter, got 22 outs, allowed only two hits and pitched to just one man more than the minimum. Kershaw won on velocity and spin-rate. Hendricks, as he usually has this year, won on the scoreboard. “As good as this feels,” said Hendricks, “we know what we got to do.”

“Everybody took a deep breath,” Fowler said about the early offense. “You never know how it’s going to start, but once that dude gets his momentum, Kershaw, he keeps it going. So we tried to take that out.”

Once again, the pitcher with the 2.37 career ERA in the regular season pitched like an impostor — even on five days’ rest. Again this October, as in his entire postseason career of 18 games and 13 starts, his ERA is right around 4.50 — for 2016 and his career. That’s twice his norm. And for a small sample size, that’s getting pretty big.

Before Kershaw exited after five innings, he had also allowed solo homers to Anthony Rizzo and Willson Contreras, a 24-year-old hunch starter at catcher by Cubs manager Joe Maddon.

In fact, Maddon also started Albert Almora, Jr., 22, in right field in place of overpaid free agent Jason Heyward ($185 million). “You just got to make some tough calls,” Maddon said.

Hendricks’s first pitch of the game actually was hit hard — ambushed for a single to right field. His next was slapped into an easy double play. After that, he pitched one of the clearest, most understated masterpieces of recent Octobers. Through 18 hitters, Hendricks had 18 outs. When Javier Baez booted a grounder at second base, Hendricks simply picked Josh Reddick off first, by a yard.

It is hard to express the relief that this crisp and slightly lopsided game provided to the town of Chicago and Cubs fans everywhere. The phrase “winner-take-all playoff game” freezes the spines of folks here because they remember, or are constantly reminded of, the Cubs’ final defeats in the NLCS in 1984 and 2003. Both were hard to believe and almost harder to watch.

In 1984, the Cubs beat the normally lowly San Diego Padres, 13-0, then went ahead 2-0 in the series before losing three straight and being eliminated. The turning point in the final game was a grounder that went directly through first baseman Leon Durham, even though he got down on one knee specifically so that misfortune could not possibly happen.

That was the day I started believing the sports curses were not entirely bunk. In 2003, when a Wrigley Field fan, Steve Bartman, became the symbol of accidental defeat, I was a convert.

This city woke up worried and stayed worried all day. “There’s angst; there’s all that kind of good stuff,” Maddon said before the game, then added the baseball understatement of the century: “It’s just a fan base that’s been waiting for a while.”

A while? The last time the Cubs won it all, the automobile and the airplane seemed like dicey fads that might soon pass. Consider: When Fox broadcasts Tuesday’s Game 1 from Cleveland, it will mark the first time a Cubs World Series game will be on television.

The hawkers on Addison and Clark streets outside Wrigley had their “Ghostbusters”-style T-shirts that read, “We ain’t afraid of no goats.” But who believes it? This North Side intersection is where baseball ghosts and goats have always met. The white “W” flag above the old scoreboard means “Win,” but it symbolizes Worry. That won’t stop now. It may double.

Starting Tuesday, the Cubs’ ability to defeat worry, or at least compartmentalize it out of existence, will be essential. The underdog Indians are actually the champions of the statistically superior league — the AL. They have knocked out the dangerous Red Sox and Blue Jays, both jammed with mighty hitters — and akin to the Cubs in both power and relative disinterest in stolen bases — with a 7-1 record in the postseason.

No two managers in baseball preach this gospel more or better than Maddon and Cleveland’s Terry Francona. But it’s an easier sell for the underdog, which Cleveland most certainly is.

Forget the past 108 years, even as every third person they meet mentions it. And forget the next 108 years, too — and their hallowed place in Cubs mythology. Because that’s about how long this team may be squeezed and hugged, as if they really were just adorable Cubbie bears. Just don’t think about it, don’t think, don’t. . .