Joel Embiid’s conditioning and buy-in will control Sixers’ success. Not what happens to James Harden.

TORONTO — We keep talking about James Harden.

We talk about how the 76ers’ success could be determined by how the Harden saga concludes.

If he stays, we think the Sixers are a notch below the Boston Celtics and Milwaukee Bucks in Eastern Conference supremacy. We believe the Sixers can compete with those teams by trading the disgruntled point guard for an All-NBA talent. And we think they’ll have a disappointing season by trading Harden in exchange for role players.

But we’re getting it all wrong.

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Joel Embiid is the key to the Sixers success. The reigning MVP is the key just like when he played with Ben Simmons, Jimmy Butler, and any other co-star you want to add.

The Sixers will only go as far as Embiid leads them.

And right now, some folks are panicking over Embiid’s disappointing start to the season.

His struggles were the main reason why the Sixers lost 118-117 to the Bucks in Thursday’s season opener at Fiserv Forum. The six-time All-Star had a better showing in Saturday night’s 114-107 victory over the Toronto Raptors at Scotiabank Arena.

Embiid finished with 34 points, nine rebounds, eight assists and two blocks. He was deliberate in his actions and played with an aggression.

So what was the difference?

“The second game, really [no] preseason, knocking off the rust,” Embiid said. “The first game of the season, so I was being extremely passive, trying to go through the offense. That was a big reason I had seven turnovers [against Milwaukee]. Tonight, I just took my time.”

The Raptors (1-2) brought extra defenders to double Embiid quickly. But he was just more aggressive. He caught the ball and made quick moves.

“I was just making the right plays, and just keeping the game simple,” he said. “But it’s the beginning of the season. Like I said, you can’t get too high, can’t get too low. Sometimes you have good night, sometimes you don’t.

“It’s all about staying balanced.”

Embiid scored 14 of his points in the first quarter on 5-for-7 shooting from the floor.

Against the Bucks, Embiid finished with 24 points on 9-for-21 shooting to go with seven rebounds and six assists and his seven turnovers. He was at his worst in the fourth quarter.

He checked back into the game with the Sixers down 94-93 with 8 minutes, 41 seconds remaining. Embiid scored just four points on 2-for-8 shooting and committed a costly turnover in that span to end the game.

Embiid was noticeably rusty all game.

He was also passive at times while trying to coexist in the Sixers’ free-flowing offense under coach Nick Nurse. A season ago, Embiid won his second straight scoring title while he and Harden dominated the ball in the two-man game.

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But struggling and needing to get in game shape at the start of the season is nothing new for Embiid.

A season ago, Embiid missed four of the Sixers’ first 10 games. Without him, the Sixers played with elite tempo and did a solid job of moving the ball. But as their best player, they need to figure out a way to maintain their tempo and ball movement with him on the floor.

Now, folks are pointing to his lack of conditioning.

There are social media posts highlighting his refusal to fight through a screen, leading to Bucks center Brook Lopez draining a wide-open three-pointer. And his poor spacing in a pick-and-roll followed by turning the ball over on a lackadaisical pass on another play are also making the rounds. That fourth-quarter turnover led to a Jae Crowder three-pointer.

All this came after Embiid only played in the last of four preseason games because of his “ramping up” process.

“It’s not the first time that this happened,” Embiid said of starting the season rusty. “It’s a long season, and we’re going to be fine. It’s the first game of the season. We can’t come in here and expect to drop 40 or 50. It’s going to come. It’s going to happen.”

The Sixers’ success depends on him being in optimal shape and continuing to buy into Nurse’s system.

He has publicly stated his love for Nurse’s system.

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Embiid is so good that he’ll get double teams, which is great for the Sixers. That will open things up for teammates. So he has to make them better in those situations by finding the open shooters and setting good screens.

And as one league’s best defenders, he has to consistently be a defensive force. But that also starts with being totally bought in.

He has to come out and aggressively defend opponents when they slide out in the perimeter. He also has to run out to disrupt wide-open, would-be shooters when he’s the closest to them. And Embiid has to position himself underneath the basket, protecting the rim.

All that requires being in optimal condition.

Embiid should play himself into shape. He’s playing the entire first quarters, which should help “ramp up” his conditioning.

Right now, his first-game struggles and effort was the result of his conditioning.

When tired, Embiid doesn’t always run back on defense. He also misses routine shots.

With the Sixers up eight in the fourth quarter Thursday, Embiid missed a 15-footer he typically makes. That came a couple of possessions after missing a routine 13-footer with his team up six. But on Thursday, they were both short.

The 15-footer could have put the Sixers up 10 points and provided the momentum to win the game.

Those misses were a sign of him being tired.

So his conditioning and being totally bought in will determine the Sixers success regardless of what happens with Harden.