It was clear that Kevin Durant’s knee injury would create problems for the Golden State Warriors as soon as the severity was announced last week. While the team with the NBA’s best record boasts more star depth than any other squad in the league, the rotation is not especially deep and isn’t necessarily equipped to withstand the loss of one of the NBA’s best players for a month or more. Add in that the injury came on just the second day of a very tough stretch of eight straight games in different cities (in just 13 days), and it was always possible that the Warriors would lose a few games without their two-way superstar.

However, those ongoing struggles without Durant have been more serious than anyone expected. Those difficulties continued apace on Wednesday night in Oakland against the Boston Celtics. A short trip home before heading back out on the road offered the Warriors no comfort. In fact, they looked downright horrible during a fourth-quarter collapse that led to a 99-86 loss, their third in five games without KD.

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For a time, it looked like the Warriors were in position to pull out a win on a night when they clearly couldn’t find their best form. Golden State led 74-72 heading into the fourth quarter and 79-78 after a Draymond Green dunk with 7:18 remaining. The offense was sputtering, but a change in fortune was not out of the realm of possibility.

Then everything went horribly wrong for the Warriors and extremely right for the Celtics. Kelly Olynyk answered Green’s jam with one of his own to start a 15-0 run that both decided and finished off the game. The Warriors didn’t score again until a Green three-pointer at the 3:47 mark, and any hope that it would start a comeback had to have felt like wishful thinking. The Warriors simply didn’t have the energy or ability to make a sustained charge.

That was never clearer than on one interminable possession in the final three minutes. Head coach Brad Stevens called a timeout at the 2:53 mark to help stop a Warriors charge, but it was what came in the minute after that doomed the Warriors. The Celtics grabbed offensive rebounds off two missed Jae Crowder threes, got a non-shooting foul from Stephen Curry on Isaiah Thomas after the second, and then finally saw Avery Bradley complete a jumper with 1:45 remaining to end a 68-second possession that felt more like a form of torture than basketball. Take a look:

ESPN’s J.A. Adande came up with the perfect comparison — it had the character of a hockey power play for Boston:

The Warriors have rarely looked worse. Facing a side well known for its rebounding struggles, Golden State could not get to a number of 50-50 balls and lacked the activity that has been one of the team’s trademarks in recent seasons.

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Frankly, the fourth quarter had more in common with the Antawn Jamison era than the Stephen Curry era. The Warriors scored only 12 points in the period and committed five turnovers against four assists, a shocking figure for a group that has made a habit of topping 30 assists all season. They looked exhausted, incapable, and just downright bad.

The timing of this slump has created big problems for the Warriors at the top of the West. With three losses in the last nine days, they now sit just 1 1/2 games ahead of the San Antonio Spurs, winners of nine in a row (including a 28-point comeback without their two best players on Wednesday). It’s not inconceivable for the Spurs to overtake the Warriors when they face off at AT&T Center on Saturday night in a game that will serve as the second half of a back-to-back for the visitors. The way the Warriors are playing, it’s hard to imagine them beating a team as strong as the Spurs. It wouldn’t even be a surprise to see Steve Kerr rest his stars, perhaps allowing San Antonio to pursue homecourt advantage on its own terms.

At this point, it’s hard to argue against giving Stephen Curry, Klay Thompson, and Draymond Green a night off. The Warriors have struggled to shoot from outside for a while now, with Curry going just 17-of-68 from beyond the arc in his last six games. Wednesday brought a 6-of-30 showing from deep, a ratio that would be glaring if it weren’t merely the worst in a string of poor shooting performances. Without Durant, the Warriors offense has looked wholly depend on shooting, and the lack of perimeter excellence has led to many iffy stretches. Golden State looks desperate for shots to go in and does not have clear control over its offensive execution.

It’s tempting to shrug off these troubles as the result of losing such an important player during an especially hairy stretch of the schedule. After all, the Warriors have a stunning record of recent success and have proven capable of besting good teams with adequate rest. For that matter, the Celtics have now won three games in a row at Oracle Arena and hold the No. 2 seed in the East.

Yet these struggles do not feel meaningless, in part because the circumstances of this season are so different from those of their record-setting 2015-16 campaign. It’s no knock against Curry to note that he has only intermittently found his paradigm-shattering MVP form this year, just as it’s fair to admit that the Warriors only made the NBA Finals last season because Thompson made so many absurd shots against the Oklahoma City Thunder. There is no guarantee that everything will work itself out simply because the Warriors aren’t used to being bad.

If nothing else, the next few weeks should test how serious the Warriors are about prizing rest over the desire to take the West’s top seed. Kerr has said the team will make sure they enter the postseason with energy and health, but the Warriors also haven’t had to worry about seeding or the effects of playing only three home games per series much in the past three seasons. Will their competitive spirit take over once they see that they’re in a fight with San Antonio? Or will they see games like Wednesday’s loss as a sign that delaying gratification is their best chance at a title.

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Eric Freeman is a writer for Ball Don’t Lie on Yahoo Sports. Have a tip? Email him at efreeman_ysports@yahoo.com or follow him on Twitter!

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