Golden State Warriors’ Andrew Wiggins and Jordan Poole get ready for practice during NBA Finals at TD Garden in Boston Mass.,, on Wednesday, June 15, 2022.

BOSTON — Conspiracy theorists believed that there was far more to the Golden State Warriors’ three closeout losses this postseason than missed box-outs or jumpers.

Golden State made about $7 million per home game in the first and second rounds of the playoffs, with that number spiking to roughly $10 million in the Western Conference finals. Some cynical NBA fans assumed that the Warriors’ closeout losses were part of an elaborate plot for majority owner Joe Lacob to pad his profits.

But for that to be true, Lacob would have to value money over winning — something his history of spending has proven false. The reality is that the Warriors have struggled in closeout games for a much less sinister reason: Eliminating playoff teams is difficult.

With their season hanging in the balance, NBA players tend to have maximum effort and focus. Few teams have been better at that than the Celtics. Throughout the season, they made their path harder than necessary, only to play their best when it mattered most.

This is a scary prospect for the Warriors, who must beat Boston one more time to win their fourth championship in eight seasons. A loss in Game 6 at TD Garden on Thursday night would force a Game 7 in San Francisco. And if the Celtics’ Game 7 win in Miami in the Eastern Conference finals proved anything, it’s that they can handle that kind of environment.

The good news for the Warriors is that they are well-versed on the importance of Thursday. Five of their rotation players — Stephen Curry, Klay Thompson, Draymond Green, Andre Iguodala and Kevon Looney — were part of Golden State’s collapse in the 2016 Finals. By squandering a 3-1 series lead to those Cavaliers, Curry, Thompson, Green, Iguodala and Looney realized that no fourth win in a playoff series can be assumed.

“Having been here six times, been in a lot of different closeout-type of opportunities, you just understand what the nerves are like,” Curry said. “You can rely on that experience, for sure.”

It also helps the Warriors that they have shown they can beat the Celtics in a variety of ways.

In Golden State’s Game 2 and Game 4 victories, Boston insisted on defending Curry one-on-one. With his supporting cast struggling, Curry was content to dominate, working off pick-and-rolls to hit an array of scoop shots, 30-footers and midrange jumpers.

In Game 5, the Celtics sent more double-teams at Curry, only for him to find open teammates. Though he failed to make a 3-pointer for the first time in 234 outings, he dished out a game-high eight assists as the Warriors won by double digits.

Golden State had an offensive rating of 119 with Curry on the floor Monday. To put that in context, Utah’s 116.2 offensive rating was the league’s best over the entirety of the regular season.

This doesn’t bode well for Boston. When Curry has an off-shooting night, he tends to post gaudy numbers in his next game.

Even if their extra pressure continues to bother Curry in Game 6, the Celtics must do a better job manufacturing offense. A Boston team that failed to score 100 points only twice in its first 20 playoff games has now not reached the century mark in three of its past four.

Much of the blame rests with the Celtics’ 78 turnovers this series, which have led to 103 points for the Warriors. Though Golden State has been sound in its rotations and man-to-man principles, Boston has often been its own worst enemy, forcing ill-advised passes and committing unforced giveaways.

Just by cleaning things up a bit, the Celtics could give themselves a chance in Game 6. A raucous TD Garden crowd offers them a decisive home-court advantage. And given their penchant for overcoming adversity this season, the Celtics aren’t likely to let a 3-2 deficit overwhelm them.

As Cameo’s “Candy” blared over the loudspeakers at practice Wednesday afternoon, Boston guard Marcus Smart danced along to the beat near mid-court. This team knows it’s at the peak of its powers when it brings the joy. Now at the brink of elimination, the Celtics want to re-channel the free-flowing style that fueled their Game 1 and Game 3 wins.

The Warriors spent much of Wednesday’s practice reviewing the adjustments they anticipate Boston might make. They were left with a strong feeling that, if they bring the proper precision and focus, they should hoist the Larry O’Brien trophy at TD Garden.

“We’re trying to have a good balance of still being locked in, and appreciating the moment and embracing everything,” guard Jordan Poole said. “We are here to win one more game, finish it and hopefully have a better plane ride back.”

But given how the Warriors have fared in similar situations recently, they know that is a significant ask. Three of their six losses this postseason came in elimination games: Game 4 against the Nuggets, Game 5 against the Grizzlies and Game 4 against the Mavericks.

Though it would be easy to blame those defeats on a lack of effort or intensity, all three — even the 39-point blowout by Memphis — were more nuanced. The Warriors are sometimes so eager to win that they force things and pile up turnovers.

In the case of that drubbing against the Grizzlies, they let some costly giveaways early snowball into an embarrassment of historic proportions. It’s now on the Warriors to strike a delicate balance in Game 6 against the Celtics: play with enthusiasm, but not so much enthusiasm that it causes problems.

This much is clear. Golden State won’t be pleased if it must fly back to San Francisco having to play a Game 7. The chance to celebrate a title in front of fans and earn another cash infusion would be nice, but the Warriors would much prefer to hush the conspiracy theorists and win in six.

“We are just going to have to play really well to win,” head coach Steve Kerr said. “It’s as simple as that.”

Connor Letourneau is a San Francisco Chronicle staff writer. Email: cletourneau@sfchronicle.com. Twitter: @Con_Chron