The way St. Louis Manager Tony La Russa, tossing a ball to fans, has handled his pitching staff has been unusual, and yet it has worked so far. (David J. Phillip/Associated Press)

There is an easy way to go about this — the business of trying to win a championship — and there is a difficult way. And the relative merits of each path are on vivid display in the National League Championship Series, which continues Sunday night with Game 6 at Miller Park, with the St. Louis Cardinals leading the Milwaukee Brewers, three games to two.

The easy path? Go out and acquire two front-line starting pitchers at the peaks of their careers. Build your lineup around two MVP candidates in the middle. Keep everyone remarkably healthy: three starting pitchers with 33 starts each, two others with 28, plus seven hitters with at least 430 at-bats. Build a lead of 101 / 2 games by late August, and coast home. Turn a unique home-field advantage into 57 home wins in the regular season and an aura of near-invincibility in October.

That was the Brewers’ path to this place, where all they have to do to reach the World Series for the first time in 29 years is win back-to-back games at Miller Park, where they had won four straight this postseason until a loss to the Cardinals in Game 2.

“We know how good we’ve been here,” Brewers Manager Ron Roenicke said before his team’s workout. “We’re confident here.”

The difficult path? Let us introduce you to the Cardinals.

Theirs was not a road anyone has ever recommended, and the Cardinals didn’t draw it up this way when they reported to spring training in Jupiter, Fla., in mid-February. You don’t set out to lose your best starting pitcher in the first week of spring training — the way the Cardinals did with ace Adam Wainwright, who blew out his elbow.

You don’t seek to pick a contract fight with your iconic player, as the Cardinals did with Albert Pujols, whose lack of an extension this spring threatened to be a season-long distraction, until Pujols and the Cardinals vowed to each other that it wouldn’t.

“We had a pact,” Manager Tony La Russa said. “We talked that first day, and there was nothing afterwards.”

And you certainly would not choose to set yourself on a 162-game trajectory that sees you hover a few games above .500 for much of the season, fall 101 / 2 games out of a playoff spot by late August, then rally with a 20-8 finishing kick that — combined with a gruesome collapse by the Atlanta Braves — gives you the wild card on the season’s final day.

“It could be a crazy ride and we end up in the World Series or winning the World Series, who knows, but no matter what happens, this group of guys is very special,” said Cardinals right-hander Chris Carpenter. “They can’t take anything that we’ve done away from us. We’ve had our backs against the wall for a good period now, and we continue to battle back.”

It makes perfect sense, in that context, that the Cardinals are taking the difficult route in trying to win the NL pennant. In La Russa’s handling of his pitching staff — full of aggressive, caution-to-the-wind maneuvering that puts his team right up against the edge of disaster on a nightly basis — the Cardinals are unveiling the perfect, best-of-seven microcosm of their season.

Through the first five games of the NLCS, no Cardinals starting pitcher has recorded an out past the fifth inning — which is typically thought to be an untenable situation. According to the Elias Sports Bureau, no team has won a postseason series without at least once getting a starting pitcher past the sixth inning. For dozens of years, the winning postseason formula has been deep outings by your starting pitchers, a brief bridge of a handful of outs by your top set-up men, and three or more outs from your closer.

For the Cardinals, the formula is more like 42 / 3 innings from the starter, a procession of relievers for the next nine or 10 outs, and an inning (at least) from closer Jason Motte.

La Russa swears that he didn’t set out to manage the NLCS in such a way, but that situations have dictated it. And the numbers bear this out. There is perhaps only one way to survive a series in which your starting pitchers have combined for a 6.04 ERA and have permitted opposing hitters a .340 batting average and .974 OPS — and that is to deploy a bullpen with a collective 1.66 ERA and opposing batting average and OPS of .164 and .516.

“That’s why I enjoy this part of the season so much,” La Russa said. “For the first four months of the season, you’re taking the long view. You [give] a little more rope [to each] hitter [and] pitcher, because you’ve got to build [their] confidence — plus, strategically, you may be short [on options]. But when you get down to where the end’s in sight, the immediacy — that’s more fun actually.”

The difficult path being the more fun one? Only La Russa would say such a thing, and only the Cardinals would attempt to make it work.