Game 3 was a disgraceful performance by the once-proud Celtics. Even though it’s not over, don’t you want it to be?

Jaylen Brown, who scored just 12 points and was 0 for 7 on 3-pointers, appeared stunned as he headed to the bench in the third quarter.Jim Davis/Globe Staff

MIAMI — A lifetime of incorrect predictions has taught me that it’s dangerous to prematurely state that any series is over. Yogi Berra was right. It ain’t over ‘til it’s over.

But man, oh, man. Don’t you just want this Celtics season to be over?

In another hail of turnovers, technicals, airballs, matador defenses, and nonstop complaints to the officials, the once-proud Boston Celtics were defeated yet again by the estimable, eighth-seeded Miami Heat Sunday, 128-102. Miami led by 8 after one, by 15 at the half, and stretched it to 33 midway through the third. At that point, it felt as if the Celtics had simply quit.

And yet poor coach Joe Mazzulla still will not say anything bad about his rollover players.

“I just didn’t have ‘em ready to play,’’ said the kid coach. “I should have . . . Whatever it was, I have to get them in a better place. That’s on me . . . I think they’re doing everything they can . . . I just didn’t execute the proper game plan. It’s on me to be better so they can play better.’’

Noble, but ridiculous. The fault here lies not with Grady Mazzulla, who may be coaching his last game Tuesday. This is on Jayson Tatum and Jaylen Brown, the faux superstars of the team. Tatum scored 14, Brown 12. The Jays shot an aggregate 34 percent (12 for 35), making only 1 of 14 threes. Each committed three turnovers.

“Tonight was tough,’’ said Tatum. “From the beginning of the game, we were turning the ball over, we didn’t shoot the ball well. It felt like we never recovered and that’s on all of us as a unit . . . As tough as tonight was, we just got to try to move on. Obviously, its a tough position. We’ve got to have some pride and bounce back.’’

“Coach is being generous,’’ added veteran Al Horford. “As a player, I take responsibility. We didn’t have what we needed to have.’’

With this, Boston’s sports spring of high expectations is almost officially over. The record-setting Bruins bowed out in Round 1 of the Stanley Cup playoffs last month and the Celtics are on the edge of an ignominious sweep at the hands of a team that had to play two play-in games just to qualify for the postseason.

Like their Causeway Street roommates, the Celtics came into these playoffs favored to win the championship. But after a couple of stunning home losses featuring late-game chaos and collapses, they lost their hearts on the way to South Beach and mailed it in for Game 3.

Now they face the impossible: they are down 3-0 with another game scheduled in Miami Tuesday.

What's next for Joe Mazzulla, Jayson Tatum and the rest of the Celtics?Jim Davis/Globe Staff

History is not the Celtics friend — even for a franchise steeped in history. No team in NBA annals has won any series after trailing, 3-0. That covers 149 series over the last eight decades. The LeBron James Lakers face the same insurmountable hurdle in their conference final vs. Denver.

This could hardly feel any worse. The Celtics appear to be broken and it’s pretty clear that kid coach Grady Mazzulla — sorry, Joe’s gotta go if this winds up being a sweep — doesn’t have the answers. Folks down near the Boston bench Sunday saw Celtic players openly complaining to their rookie boss.

Folks at the goofy ESPN Analytics’ Basketball Power Index certainly liked the Green Team coming into this series. Before Game 1, they stated that the Celtics had a 97 percent chance to win the series. After losing two at home the ESPN geeks doubled down, claiming the Celtics still had a 65 percent chance to win the series. In Vegas, the Celtics were 4½-point favorites for Game 3.

So what are the nerds and wiseguys saying now that the Heat lead, 3-0? Are the Heat getting any national love yet?

Built in the image of Pat Riley, and shaped by Hall of Fame-level coach Erik Spoelstra, the Heat evidently are just plain better than the Celtics. And so much tougher. Featuring seven undrafted players, they are Janis Ian’s team: “Those whose names were never called when choosing sides for basketball.’’

For more than a week we’ve been looking at the Celtics roster, and the Heat roster, and coming away saying that the Celtics have the better team. It’s certainly true the Celtics were a better regular-season team, going 57-25, 13 games better than Miami’s 44-38.

The Celtics officially (according to NBA media) have two of the NBA’s top-10 players in Tatum and Brown. The Heat only have one, Jimmy Butler. One of Miami’s starters, the undrafted Max Strus, was cut by the Celtics in 2019 to make room for the immortal Javonte Green.

Now, barring the greatest comeback in NBA history, the 2022-23 Celtics are destined to be remembered as posers and front-runners. They waltz around as if they’ve been to the mountain top even though they’ve never reached the summit. They never seemed particularly rattled or urgent. They turtle and turn over the ball in close games. In these playoffs they are 0-6 in games within 5 points in the final three minutes.

“We’re not out yet,’’ said Horford. “We’re still kicking.’’

“I’m going to fight to the end,’’ added Brown.

I won’t count them out. I didn’t trust them when they were really good and I won’t trust them now that they are really bad.

It’s the ghost of the 2004 Red Sox.

When the Curse-busting Sox fell behind, 3-0, to the Yankees, losing the third game of the ALCS, 19-8, at home, I buried them, writing this on Page 1 of the Oct. 17 Sunday Globe: “So there. For the 86th consecutive autumn, the Red Sox are not going to win the World Series.’’

Jimmy Butler had just 16 points Sunday night, but had plenty of reasons to smiles, as Miami took a 3-0 lead in the series.Lynne Sladky/Associated Press

You know what happened. That very night a hungover Kevin Millar started telling everyone, “Don’t let us win tonight. If we win tonight, we got Pedro coming back and then Schill and then anything can happen in a Game 7.’’

And it all happened.

To this day, the Globe has not run a correction for the incorrect fact stated on Page 1 of that Sunday newspaper. It would have been a classic, something like, “Because of a reporter’s cynicism, it was incorrectly stated in the Oct. 17 Globe that the Red Sox were not going to win the 2004 World Series. The Red Sox did, in fact, win the 2004 World Series. The Globe regrets the error.’’

So no declarative statements about the pathetic Celtics today. Too soon. It ain’t over. And Sunday’s 128-102 loss felt a lot like 19-8 at Fenway in October of ‘04.