IT’S BOONE OR BUST!

Wild-card game against A’s is Aaron’s first true test as Yankees manager

In his rookie season as a manager, Aaron Boone’s Yankees won 100 games.

And we still don’t know if he can really manage.

But we do know this: He’s got guts. Either that, or the people making his decisions for him do.

Because by choosing Luis Severino to start Wednesday’s one-and-done Wild Card game against the Oakland Athletics, Boone has put himself directly in the crosshairs in what will essentially be the first important game he has ever managed.

The reasoning is understandable — despite some hiccups, the Yankees bullpen is still one of the strongest units on the team, and by starting Severino you preserve J.A. Happ, a Red Sox killer, for two of the five ALDS games against Boston.

But what if you don’t get that far? What if Severino fizzles out the way he did in the first inning of last year’s wildcard game against Minnesota? Will Boone have the intestinal fortitude to pull his ace after recording just one out the way Girardi did last year?

And by they way, the combination of Severino and Gary Sanchez behind the plate hasn’t just been oil-and-water. More like gasoline and match.

Those questions make Wednesday night’s game incredibly intriguing, and for Boone, incredibly risky.

Now, despite winning more games than any Yankees team has since the 2009 World Championship team, and enough to have wonpthe AL East in each of the previous eight seasons, the verdict on Boone’s inaugural season as Yankee manager will come down to a single game.

Chances are, it would have anyhow, because even though George Steinbrenner has been dead for eight years now, his philosophy lives on in the hearts and minds of his front office and the fan base: Anything less than a world championship constitutes failure.

But if the Yankees fail against the A’s, it will confirm in some minds the feeling that has lurked as an undercurrent to this entire season: That despite winning all those games, something has not been quite right with this team.

For many, it seems, what is not quite right is Aaron Boone.

For some, he’s too laidneed, back, too SoCal cool to bring the kind of fire the Yankees the way Billy Martin and Joe Girardi did. For others, his lineup configurations are suspect, his bullpen decisions at times head-scratchers and his tendency to sit players the day after they’ve had a big game is exasperating, even infuriating.

One of his go-to lines, about “keeping guys relevant,’’ smacks to some of the “everybody’s a winner’’ school of participation awards and endless positive reinforcement.

Imagine what those critics will be saying if the 2018 Yankees wind up playing just one more game than the 2018 Mets.

Of course, there’s no question Boone will be back next year, regardless of what happens Wednesday night. His