Maybe the outcome of Game 1 in the Eastern Conference Finals was preordained.

The NBA’s new kids on the block were not going beat the Celtics with an OG member of “New Kids On The Block” cheering courtside at TD Garden.

Especially one wearing a “Boston” hoodie.

Donnie Wahlberg joined “Boston Royalty” (ESPN’s words) who witnessed hysteria and history Tuesday night at TD Garden. Among them, new dad David Ortiz. And Drake Maye, who was allowed to stay up past his bedtime on a school night.

Wahlberg is a TD Garden regular. Tuesday, he scored almost as much airtime on ESPN as Joe Mazzulla.

That’s a plus – not just for the “Blockheads.”

The less we see of the Celtics coach this time of year, the better. Tuesday, Mazzulla kept his cool. Used his timeouts. And drew up the play that pushed the game into OT.

Meanwhile, Pacers coach Rick Carlisle took the metaphorical bullet for his team’s loss for bungling his team’s final inbound play of regulation.

The Celtics delivered another win for the ages with a 133-128 overtime decision over the Indiana Pacers. This is not a case of boys to men; the Celtics are adult enough to win it all this year.

In this series, the Celtics have been cast as playoff-tested veterans. And the Pacers are the Celtics of 2022.

What this version of the Celtics have lacked – call it “The Right Stuff” – at crunch time was the grit and balls to either win a game they should have lost, or at the very least not lose a game they should win.

Tuesday, the Celtics finally won a game in which they failed throughout, or for at least the first 47 minutes, 50 seconds.

Hangin’ tough.

This time, the action wasn’t seen on a VHS tape. But live on ESPN in high-def.

Just as important for the “Banner 18 Or Bust Crowd,” the best players on the Celtics played their best at the game’s most important moments.

Brown’s 36 points were just the start. He added 12 rebounds and hit 10 of 12 free throws. Boston was +20 with him on the floor.

He’s the House Alpha. Brown sports a middle-aged dad scowl on his 27-year-old face when the situation demands. You’d better root for the patriarchy this time. Because without Brown being Indianapolis’ daddy, the Celtics will be headed to Cancun, and not Minnesota or Dallas, for the NBA Finals.

Brown Tuesday delivered the most impactful pick since Malcolm Butler’s. He poked away a pass from Andrew Nembhard bound for Pascal Siakam.

Brown got just enough on the pass to send it out of bounds off Siakam. On the inbound play, everything that usually goes wrong for the Celtics in these situations went the other way.

Jrue Holiday was in sync with Brown on the inbounds pass. Brown floated to the corner and launched a blind 3-pointer while having his personal space violated by Siakam.

“Bang. Bang.” Thank you, Mike Breen.

Game tied 117-117. Soon, Jayson Tatum would “wake up” – Brown’s words, not mine – and produce 10 points in the overtime. His 3-point dagger from atop the key with 42.8 seconds to play iced it.

Tatum didn’t score in the final 9 minutes of regulation, but contributed just enough on defense to facilitate the eventual outcome.

The Celtics may be taking a backstreet to Banner 18.

Save for the Pacers, the rest of the East crumbled like sandcastles at high tide on Hampton Beach.

Injuries. Age. Youth. Mistakes. Whatever.

Out West, the Nuggets Dynasty was abruptly cancelled. The Lakers no-showed. Steph Curry is ancient history.

Irrelevant decibels.

Do the Celtics get credit for two trophies after beating the 1969 or 1984 Lakers? Or 1.5 trophies for icing Banner 17 by ousting LeBron James and Kobe Bryant in 2008?

Nope.

Banner 18, if it comes next month, means just as much as its predecessors.

Step by step, the Celtics are proving to themselves and everyone else that we may be watching the new edition of the “Tatum and Brown” show.

For all the daily caterwauling on the airwaves and across social media, the Celtics are 9-2 in this postseason. Best in the NBA. They are doing as well as can be reasonably expected.

We’re not getting soft. Our standard hasn’t changed. Champs or chumps. Period.

Do. Or do not. There is no try. Yoda may have been the greenest of Green Teamers.

Still, the Celtics dispatched the Heat and Cavs in five, respectively. That shaved 3 grueling games off their road to the Eastern Conference Finals vs. last year.

Boston won Game 1 of the Eastern Conference Finals at home – no mean feat for this team.

Yes, the Pacers gave it away.

And this time, the Celtics took it.

Instead of chucking up a brick at the buzzer.

Or turning over the ball on the last possession.

Call it a “building block.”

State law prohibits any discussion of the Celtics without a listing of grievances.

Here’s a quick Game 1 recap:

The Celtics can’t win a title without Kristaps Porzingis.

The bench was outscored 30-13.

Boston missed 30 of its 45 3-point shots.

Sam Hauser was -8 and scored 0 points in 9 minutes.

The Pacers shot 53.5% from the field and 37.1% from 3.

The Celtics blew a 13-point lead in the second half.

With numbers like these, the outcome would have gone in one direction last season.

That being a soul-crushing home loss.

Perhaps, those days have gone “bye, bye, bye.”

Yes, Donnie, we know that’s the other guys.

Maybe these Celtics are becoming the other guys, too.

Bill Speros (@RealOBF and @BillSperos on X) and can be reached at bsperos1@gmail.com.