The most difficult part about being a manager must be deciding how much recent history you are supposed to accept, and how much you are supposed to reject. Mike Tyson always said everybody’s got a plan until you get punched in the face, but the thing about baseball is that the fact that you just got punched in the face doesn’t mean your plan isn’t working … or, worse, that not getting punched in the face just yet doesn’t mean that it _is_.

• NLDS presented by Utz, Game 4: Today, 3 p.m. ET/2 p.m. CT on TBS

You can do everything right and have it blow up on you; you can do everything wrong and emerge victorious anyway. The only constant is being praised as a genius when you win and being called a moron when you lose.

In Game 3 of the National League Division Series on Sunday afternoon, you can be forgiven for thinking that Cardinals skipper Mike Shildt, managing in only his third postseason game, had somehow wandered in from another era. He left his starter, 38-year-old Adam Wainwright, in for 120 pitches, even though, as masterful as he had been for the first seven-plus innings, he clearly had lost it about four batters before he was actually pulled. Shildt treated Wainwright as if he were Jack Morris or even Old Hoss Radbourn -- he pitched so well that he deserved to finish this.

Shildt survived the moment thanks to a well-placed line drive from Freddie Freeman off Andrew Miller, only to raise eyebrows again the next inning, going to his “closer” Carlos Martinez, even though Martinez has been slowly falling apart for several weeks now, barely escaping jam after jam of his own creation since deep into the regular season, up to and including giving up three runs in Game 1 of this series.

But to Shildt, Martinez was his guy, even though he’s not the best reliever on the Cardinals and probably not the second- or third-best. Shildt did not survive this moment, and Martinez gave up three more runs, ruining Wainwright’s incredible performance and basically turning this entire series upside down in the span of eight minutes. The Cardinals would have had two chances to clinch, one at home against a starter on short rest and the other with second-half monster Jack Flaherty. Instead the Cards are facing elimination … and, let’s be honest, have the look of the walking dead.

Shildt’s managerial style was traditional, almost formalist, like it was from an old-school baseball movie about tough guys. But what’s so strange is what has distinguished Shildt all season. The reason he might win the NL Manager of the Year Award and the reason he has been such a breath of fresh air from his predecessor is that he is such a flexible, non-traditional manager. Shildt has routinely benched established stars for fresh blood if they’re not producing; sitting the respected but struggling Matt Carpenter for Tommy Edman is one of the primary reasons the Cardinals emerged from the NL Central pack in September.

Shildt's embrace of analytics, particularly on defense, has distinguished him as the rare manager who never played baseball professionally. Plus -- and this one is crucial -- Shildt has been innovative with the Cardinals bullpen, using whichever pitcher is best for the situation rather than being locked into set roles.

Giovanny Gallegos has been the Cardinals’ best reliever all season, but Shildt didn’t just call him the closer and be done with it. Instead, he used Gallegos whenever the situation called for it, whenever the highest-leverage at-bats arrived. After Jordan Hicks -- the Cards' best reliever entering the season -- went down in June, Shildt didn’t just install Gallegos as closer; he put Martinez there, not because Martinez was the best pitcher, but because putting him there allowed him to continue to deploy Gallegos as needed.

It was a terrific plan, and it worked. But the thing about plans is that if you’re not careful, they can ossify into dogma. Shildt used Martinez as his closer so long that he forgot he’s not in fact his best pitcher; the unconventional manager slowly transitioned into the "He’s Our Guy" traditionalist. It nearly cost Shildt in Game 1 and it absolutely did in Game 3. He may not have the good fortune to even have the opportunity to correct his mistake. It may now be too late for that.

That’s the thing about plans: They work until they don’t.

Maybe the trick in the postseason is not to have a plan at all. In the new film "Parasite," a character defends his lack of ideas to save him from his current predicament by saying, “You know what kind of plan never fails? No plan. No plan at all. You know why? Because life cannot be planned.”

Perhaps Shildt’s mistake as a new postseason manager is to treat the playoffs as if it is anything like the regular season, as if what worked during the regular season has any sort of connection to what might work in the hothouse that is October. Leaving Wainwright in, bringing in Martinez to close, that’s trusting your guys in August, honoring veterans, putting your guys where they want to be.

However, honor and trust are privileges and luxuries in October. In the postseason, you just have to start throwing whatever happens to be laying nearby -- kitchen knives, lamps, sinks -- at the scary bad guy until he finally stops moving.

The favorites in each of these NL Division Series are all heavy favorites -- the Braves were six games better than the Cardinals this year -- and perhaps the only strategy to bridge the gaps is to flail and gnaw and scratch. Nationals manager Dave Martinez, also in his first postseason, is using every pitcher available (and a few not available) to fill every possible gap. Stephen Strasburg in long relief? Patrick Corbin in middle relief? Whatever works! Get the outs!

This hasn’t always worked: Corbin got shelled in Game 3 on Sunday night, but you can’t blame Martinez for trying to manage around his bullpen, his team’s most obvious weakness. And just last year, we saw Alex Cora manage this way for the Red Sox and win a World Series in the process. Bottom line: Martinez is maneuvering as fast as he can. Shildt is dancing with the one who brung him.

Shildt has stuck to a plan that got him this far but no longer works. He may adjust and come up with a new plan, but there’s no assurance that one will work, either. It’s October. He’s facing a superior team. The only plan is no plan. This is no time for strict edicts.

Five years ago, after former Cardinals manager Mike Matheny brought in Michael Wacha, who hadn’t pitched in a month, to give up a walk-off home run that ended the 2014 NLCS, I wrote that Matheny “managed this NLCS like he had all the time in the world. Now he has none.”

Shildt is out of time. What worked before is irrelevant. Time to start throwing the sink.