Leon Rose must decide what Knicks really are in loaded East

The Celtics earned banner No. 18 Monday night, finishing off a season in which they went a combined 80-21 in one of the great start-to-finish years you’ll ever see. They went 16-3 in the playoffs. They not only never faced a decisive game, they were never worse than tied 1-1 in any of those romps against the Heat, Cavaliers, Pacers and Mavericks.

That makes it seven titles for the Celtics since the Knicks won the second of their two championships in 1973. And there will be plenty of Knicks fans who will argue that, at the least, the Knicks would’ve given the Celtics a better run than any of the four teams Boston vanquished.

Maybe they would’ve.

Maybe not.

And that’s one of the problems the Knicks face as they now officially relaunch their quest to close the gap between themselves and the Celtics. Because it’s impossible to calculate with any kind of precision just how vast that chasm is.

More to the point, it’s difficult — very, very difficult — to shake from the consciousness the 27 days connecting Jan. 1 and Jan 27. Twenty-seven days in which the Knicks looked as good as any team in the NBA: 14 games played, 12 games won. Boston was 9-5 in that stretch. Dallas was 6-7. Oklahoma City was 10-4. Denver was 9-4. Minnesota was 8-7.

Only the Cavaliers, at 10-2, approached the Knicks in that time, and we saw as the season wore on that the Cavs were a house of cards and did a lot of their regular-season damage against the NBA’s dregs.

Among those 12 Knicks wins in that halcyon stretch was a 112-106 win over the Timberwolves on New Year’s Day, a game in which they jumped to a 16-point lead after three quarters. Four nights later they throttled a full-strength 76ers team in Philadelphia by 36 points. The only losses were a four-point at Dallas in which they waited a little too long to make a comeback, and a four-point loss to Orlando at the Garden in which they blew a seven-point fourth-quarter lead, the only real stinker in the bunch.

And, of course, there were the two games that capped the 14-game, 27-day run, when they obliterated both participants in the previous year’s Finals within two days of each other at the Garden: 122-84 against the Nuggets, 125-109 against the Heat.

When Knicks fans think of this year’s team, this is the version they invariably remember, coinciding with OG Anunoby’s arrival, a streak put together despite the absence of Mitch Robinson. Could that team have given the Celtics a series?

Maybe they would’ve.

Maybe not.

And that’s what Leon Rose has to calculate in the weeks ahead. It says here that if Julius Randle hadn’t been lost for the season on Jan. 27, if Anunoby hadn’t missed a bulk of games across the next two months, the Knicks surely would’ve won more than the 50 games that eked them into the No. 2 seed, meaning the last week of the season could’ve been used as a way to rest people and reincorporate Robinson into the rotation.

They still would’ve needed to beat the Celtics four out of seven, knowing Game 7 would’ve been in Boston. I know this: I would’ve liked to see that series, with those teams, in the alternatingly frantic and maniacal settings of TD Garden and Madison Square Garden.

So, knowing all of that, do you run it back if you’re the Knicks?

If you’re going to do that, you first need to lock up Anunoby, whose impact was pronounced even after Randle went down, the Knicks going 26-5 (not counting his cameo in the Game 7 loss to Indiana) with him in the lineup, including 13-3 without Randle.

It may be impossible to bring Isaiah Hartenstein back, unless he’s willing to accept a steep hometown discount. But this is offset by the hope (if it’s not an illusion) of a healthy Robinson and also this: The Knicks developed Hartenstein from a useful player to an attractive asset in two years; can they find another version at a fraction of the cost?

The biggest question, in many ways, is Randle. It took Randle a few games to completely blossom once Anunoby arrived, but he played his best ball of the season with Anunoby as one of his wingmen: 24.9 points, 8.3 rebounds, 5.3 assists. In the big picture, shutting him down was the wisest course of action, but it will take a few weeks of rugged NBA life to fully test that shoulder.

And the one question that shadowed Randle — can he be the best player on a title contender? — no longer applies because Jalen Brunson is now the clear alpha dog here.

That makes it tempting. Of course, by October, the Celtics will be hungry to defend their title. The 76ers could have Paul George or Jimmy Butler on the roster. Doc Rivers insisted Dame Lillard was never in top shape this year; he and a fully reloaded Giannis Antetokounmpo will be formidable in Milwaukee. And it’s not like the Pacers and Magic will be any less athletic, or less dangerous. Heat Culture is always lurking.

And that’s just to get out of the East.

So many questions, and so little time. Rose has presumably been waiting for one precise moment in time to strike and splurge his assets. Maybe it’s time. Or maybe he wonders, as we wonder, what the varsity Knicks might’ve looked like against the Celtics. And maybe he’d like to find out.