Before the season, Mike D’Antoni decided to dispense with the pretense and make James Harden his starting point guard. Sure, Harden had already served as the Houston Rockets’ primary ball-handler and playmaker, dominating time of possession and leading the team in assists. But he typically only got going after Patrick Beverley (or Ty Lawson, or Pablo Prigioni, or Jeremy Lin, or Aaron Brooks) had brought the ball up first.

Playing Harden at point, D’Antoni reasoned, would cut out the middleman. Getting the ball in his hands as early as possible would save Harden the fighting that came with breaking free of a defender to catch a pass before he could initiate the action. He could make things easier for Harden, which he hoped would make things easier for Houston, by entrusting total control of his spread pick-and-roll offense to the All-Star scorer.

For six months after D’Antoni tossed him the keys, Harden drove the Rockets beautifully, blowing past opponents and maneuvering around obstacles en route to 55 wins and a brilliant individual campaign that could see him named the league’s Most Valuable Player. Over the final 77 minutes of the Western Conference semifinals, though — the last six full quarters and Game 5’s fateful overtime session — Harden lost his grip on the steering wheel, wrapping the Rockets’ title hopes around a telephone pole.

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Harden followed up his bitter close to Houston’s Game 5 loss — 3-for-11 shooting with six turnovers after halftime, a scoreless final eight-plus minutes — with an utterly punchless and staggeringly inert performance in a must-win Game 6. He scored just 10 points on 2-for-11 shooting, and paired his seven assists with six turnovers.

He fouled out, too, exiting the game with 3:15 left in the fourth quarter to what might best be described as a perfunctory standing ovation from what fans remained after a mass exodus — one issued out of a sense of propriety, in appreciation of his larger body of work, but done pretty begrudgingly, given what those fans had just witnessed over the preceding four quarters.

The 10 points matched a season low for Harden, and set a new postseason low as a Rocket. The Rockets were outscored by 28 points in Harden’s 36 1/2 minutes of floor time, his worst plus-minus mark of the season, and his worst in the playoffs since Game 3 of the 2015 Western Conference Finals. Houston’s 75 points were the second-fewest scored by any Rockets team since Harden’s arrival, and three under their previous postseason low in the Harden era.

“You’ve got to take it for what it is. Everything falls on my shoulders,” Harden said during his post-game press conference. “I take responsibility for it. Both ends of the floor. It’s tough, especially the way we lost, at home, for Game 6. But it happened, and now we move forward.”

Facing elimination against a Spurs team playing without its own MVP candidate, forward Kawhi Leonard, and injured starting point guard Tony Parker, the Rockets needed Harden to deliver a game worthy of a superstar. Instead, he turned in what was, given the stakes, perhaps his worst game in a Rockets uniform.

It’s in the running, at least. Harden’s Game 6 Game Score — a stat derived from the box score and developed to offer a “rough measure of a player’s productivity for a single game” — was 0.7. Only twice in his Rockets career has he produced a lower Game Score, and not since March of 2014. As a reference point, in Game 5 of the 2015 Western finals — the one where the Golden State Warriors eliminated the Rockets and Harden set the NBA record for most turnovers in a playoff game — his Game Score was higher than this (1.0).

“Some nights, life hits you in the face,” D’Antoni said after Thursday’s game.

Harden seemed disconnected, frayed, multiple steps slow and a beat or two out of sync with his teammates from the early stages of Game 6. He threw lazy passes, sauntered into pull-up 3s that he hit at just a 28.7 percent clip this postseason, and rarely resembled the game-breaking offensive weapon who led the league in assists and finished second in scoring during the regular season:

The Spurs deserve credit for doing their part in ruining Harden’s night. Jonathon Simmons, who stepped in for Leonard at small forward, was tenacious at the point of attack, and Danny Green, Patty Mills and Kyle Anderson, among others, pitched in when they drew the top assignment. Harden praised San Antonio after the game for doing “a really good job of corralling, showing bodies [and funneling him toward] their bigs at the rim,” where the length of Aldridge and Pau Gasol bothered him as he tried to finish.

And yet …

Harden didn’t take his first free throw until the 6:18 mark of the first quarter. He didn’t attempt his first field goal until the 6:19 mark of the second, and finished the first half with just five points and only two shots in 16 minutes before the Rockets headed into halftime down by 19, serenaded by boos from the stands at Toyota Center. He didn’t grab his first rebound until nearly five minutes into the second half.

All season long, Harden imposed his will on opposing defenses and left his fingerprints all over every game he played. In the Rockets’ most important game of the season, though, it was like he was barely there.

“I really just didn’t have a rhythm at the beginning of the game,” Harden said after the game. “I feel like I was making some passes, and we just didn’t knock down shots, or whatever the case may be. As a team, as a unit, we didn’t really have a rhythm, and they capitalized on that.”

It was a jarring no-show, the kind that makes you wonder whether something significant is wrong. Was Harden sick?

“He’s been battling a cold, but nothing that I know of,” D’Antoni said after the game. “You’d have to talk to him.”

Maybe he was running through everything at half-speed because he was nursing an injury. Or maybe it was fatigue — not just the 43 minutes he played in Game 5, but the accumulated wear-and-tear of playing 81 games and ranking third in the league in minutes.

Asked if he was hurt or worn down, though, Harden instantly shook his head.

“I’m good,” he said. “I’m good.”

If Harden wasn’t sick, or hurt, or tired, then … well, what the hell happened?

“You know, I don’t really want to — if it’s OK with you guys — litigate what just happened,” D’Antoni said after the game. “It just … it happens.”

As some observers have noted, it, or something like it, has happened to Harden in the playoffs a few times before.

During his Sixth Man of the Year run with the Oklahoma City Thunder, he went 4-for-20 in Games 3 and 4 of the 2012 NBA Finals against LeBron James and the Miami Heat, coming up small in the games that helped propel Miami to the title. He shot 37.6 percent from the floor in the Rockets’ opening-round loss to the Portland Trail Blazers in 2014.

After two brilliant games to open up the 2015 Western Conference Finals against Golden State, he went 3-for-16 from the floor in a blowout Game 3 loss and 2-for-11 with an NBA-playoff-record-setting 13 turnovers in the closeout Game 5. After Stephen Curry sprained his knee sliding to the court in Game 4 of 2016’s opening round, Harden failed to seize the opportunity, finishing 4-for-13 from the field as the Steph-less Warriors unleashed hell in the second half before eliminating Houston in five games.

And now, Game 6 — a stunted and stunning affair that went crooked quickly and never straightened, leaving Spurs coach Gregg Popovich at a loss when he shook Harden’s hand after the final buzzer.

“Honestly, [Pop] said he didn’t know what to say,” Harden said. “You know, how great of a year I had, how great of a year our organization had. And I just told him congratulations, best of luck next round, and continue to be great.”

Harden, too, will continue to be great. He’s too skilled, too committed and too determined not to be, and he’s still squarely at the peak of his powers, three months removed from his 28th birthday. But the way he finished this series — going from tied 2-2 and up at halftime of Game 5 to smoldering rubble by the third quarter of Game 6 — is going to be tough to stomach, difficult to parse, and tough for a tactical thinker like Harden to get over.

During his final presser of the playoffs, a reporter asked Harden how he moves on from this. He couldn’t help but offer a defeated laugh.

“Well, we’ve got a whole summer for me to put it behind,” he said. And then, after a pause: “For us to put it behind us.”

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Dan Devine is an editor for Ball Don’t Lie on Yahoo Sports. Have a tip? Email him at devine@yahoo-inc.com or follow him on Twitter!

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