The Celtics took care of business in the dreaded play-in game. Now? It’s Kyrie Irving and the Nets

TD Garden cheered on Jayson Tatum, who returned the favor after his 50-point game.Jim Davis/Globe Staff

This was like an Oscar nominee showing up at a casting call for a small part in a B-list film, then being told he or she would have to read for the part. And maybe not even get the job.

The dreaded play-in game.

Nobody wanted the Celtics season to come to this.

The good news is that the Celtics passed the audition. Jayson Tatum, who earlier in the day said, “We believe in ourselves, still,’’ exploded for 23 third-quarter points en route to a 50-point night and led the Celtics to a 118-100 victory over the Wizards to push Boston into a first-round, best-of-seven series with Kyrie Irving, Kevin Durant, James Harden, and the second-seeded Brooklyn Nets. The Celtics were swept by the Nets during the regular season, losing three games by an average of 17 points.

So there. A Celtics team that played in the conference finals in three of the last four seasons . . . a team of great expectations that opened the year with visions of contending for a title . . . trudged to the New Garden Tuesday for a gimmick game and blasted the Wizards off the parquet after falling behind by 8 points in the first half (For the record, play-in games count as neither regular-season nor playoff games; they are their own category). After all the bad stuff that has happened, there will be more basketball at the Garden this spring. Maybe even a real Garden sellout.

Jayson Tatum dominated in the third quarter, scoring 23 of his 50 points on the way to the win over Washington.Jim Davis/Globe Staff

“It’s really hard to make the NBA playoffs,’’ said Celtics coach Brad Stevens. “Every year presents challenges, some more than others. We’ve been through a lot, so we’re hardened in a lot of ways. To have to play tonight, just to earn a right to play what is probably the most talented team that’s been assembled since I’ve been in the NBA, takes a lot of effort. Those guys are the best of the best. We’re going to have to play great and play together and be really sound on both ends of the floor.”

The Celtics and Wizards had the late slot for the historic contrivance Tuesday night. Boston and Washington did not tap off until after 9 p.m.

The Celtics struggled early and trailed by 2 at halftime, but Stevens must have imported Ernie Adams for the pep talk at intermission. Tatum took over in the third and Boston led, 90-80, after three. The Celtics put it away fairly easily in the fourth. Tatum made 14 of 32 floor shots and was 17 for 17 from the line with 8 rebounds and 4 assists. Wouldn’t you love to know what Larry Bird thinks about this kid?

Let the record show that there already has been plenty of shade thrown on the Green Team from New York and the rest of NBA America. Disrespect dropped on the heads of the Celtics Tuesday when the vaunted New York Post headlined its Nets playoff preview with, “BRING ON BOSTON — Nets will likely roll whoever the opponent, but Wizards the far more dangerous foe.’’

Riding the skills of veterans Bradley Beal and Russell Westbrook, the Wizards were the NBA’s flavor of the week coming into Play-In Tuesday. Beal battled Stephen Curry for the scoring title in the final weekend of the regular season and is best known to Boston fans as Tatum’s mentor when the young Celtics star grew up in St. Louis. Beal averaged 40.7 points in three regular-season games vs. the Celtics.

Back in the day, Westbrook was part of the Oklahoma City wagon with Harden and Durant. Perhaps the greatest rebounding guard in league history, in 2021 he surpassed Oscar Robertson’s record for career triple-doubles (Westbrook has 184 and counting).

Washington's Russell Westbrook goes strong to the basket in the second quarter of Tuesday's game.Matthew J Lee/Globe staff

Down in Bristol, ESPN’s Jalen Rose told the Post, “The Celtics were down double digits in almost 55 percent of their games. No Jaylen Brown for the rest of the year. Obviously, Tatum is an outstanding player, but I’d much rather see the Wizards and Brooklyn.’’

Indeed, on paper the Celtics look like an easier opponent than almost anyone still playing. Washington won 17 of its last 23 regular-season games, while the Celtics limped to the finish. Blaming injuries, COVID-19, and referees while dropping six of the final eight, the Celtics finished a sad, symmetrical 36-36. Along the way, they lost Brown to a wrist fracture. Complete capitulation seemed just around the bend.

Not quite. The Celtics delivered a message that they are not quitting. Not yet. At least not until they get a couple of shots at Kyrie and Co. (Maybe the Celtics can show the long-awaited Kyrie appreciation video when the Nets come here for Game 3 of this first-round series).

The Wizards came out ice cold and the Celtics led, 27-21, after one as Beal and Westbrook were virtual no-shows. It was play-in drama at its worst. The immortal Ish Smith, who has played with 12 NBA franchises, came off the bench and gave Washington great energy. Ish Smith: play-in legend.

The Celtics came out clanging in the second and Washington’s bench sparked a 21-7 run that pushed the Wizards to an 8-point lead. Westbrook had 13 rebounds in the first half and the Wizards led by 2 at intermission.

Everything changed after halftime with Tatum and Walker leading the charge. The Celtics blew the Wizards off the court.

So, now we get Celtics-Nets. Boston will be a huge underdog. Maybe it’s better that way. It certainly brought out the best in Tatum and Co. Tuesday night.

’'I give our guys a ton of credit,’’ said Stevens. “It has not always been all roses this year . . . But they just stuck together. Tonight there was a renewed sense. We played a lot better than we’ve played and I give our guys a ton of credit for that.”