I first noticed it in the third quarter of Hawks-76ers Game 2. Joel Embiid, Philadelphia’s fantastic big man, was laboring. He’s a bruiser who no longer wanted to be physical, whether because of his bad knee or fatigue (or both). Embiid seemed to be trying harder to get foul calls than going to his deep bag of moves.

Embiid looked beaten down when he went to the bench near the end of that period. But the Hawks let him off the hook. Sixers reserves extended Philadelphia’s lead to 20 points, so Embiid stayed on the bench until late. He no longer had to work hard for the Sixers to win the game.

The Hawks did not let Embiid off so easily in Game 4 on Monday night at State Farm Arena. Embiid would have to work hard late to lift the Sixers to victory. He tried, but couldn’t. The Hawks won 103-100 to tie the best-of-seven Eastern Conference semifinal at two games each.

It once looked like the Hawks had no answer for Embiid in this series. Now they head to Philadelphia for Game 5 on Wednesday with a proven plan for limiting his impact.

“Making his job tougher,” Hawks center Clint Capela said after Game 4. “Contesting everything. Make him work. I saw that whenever we wear him out, everything becomes tougher for him.

“That’s how I know it’s a long series. When the fatigue comes in, it’s a different ballgame.”

It’s a different series for the Hawks now. A big question before it started was how effective Embiid could be when playing with what the Sixers say is slightly torn cartilage in his right knee. Embiid seemed to provide an answer in the first three games. He wore out the Hawks while averaging 35 points with a 56.7. effective field-goal percentage and 10.3 rebounds.

By the second half of Game 4, the Hawks were wearing out Embiid. He missed all 12 of his shots in the half. Per ESPN Stats and Info, that’s the most attempts without a make in a playoff game since Michael Jordan was 0-for-11 in the first half of Game 4 of the 1997 East finals.

Embiid’s final shot attempt of the game made it clear he just didn’t have it. With the Sixers trailing 101-100, Embiid had a relatively clean look at the basket for a layup. He missed it badly, and the Hawks closed out the victory.

“I’m just trying to do the best I can,” Embiid said afterward.

In a weird way, it might be better for the Hawks if Embiid is out there doing his best. The Sixers run their offense through him, and the Hawks have seen how he can dominate. Embiid can do it all with the ball: score in the post, bully his way to the basket, make midrange jump shots and 3-pointers, pass, draw fouls.

But it’s clear now that Embiid can perform at his normal level for only so many minutes. In Game 4, the Hawks finally made it as hard as possible for Embiid when he’s on the floor. Just as important, they didn’t allow him a second-half breather. Their 13-point halftime deficit was down to two points by the end of the third quarter. They were behind four points when Embiid checked back in for the final 7:24.

I wondered if Hawks interim coach Nate McMillan tries to assess Embiid’s physical condition when deciding on his defensive strategy against him.

“No, no,” McMillan said. “It’s just pretty much (based on) what Embiid is capable of doing when he catches the ball in a certain spot. We’re not really looking at so much fatigue. He was able to continue to play (Monday) night.

“They were getting him the ball in his spots, but I thought we did a good job of make him work and try to deny his catch. There are certain spots on the floor where we need to make reads as far as how much help to give.”

The Hawks have appeared confused on that matter at times during this series. Help defenders seemed unsure of if, or when, they should run at Embiid. The Hawks set half-hearted traps against Embiid, allowing him to easily spin away or pass. The Hawks were getting the negatives of scrambling their defense without the positives.

That changed in the second half of Game 4. Capela gives up about 40 pounds to Embiid, but he dug in and pushed Embiid farther from the basket on post-ups. Hawks help defenders came at the right moments. Embiid had his preferred options limited. He didn’t have it in him to make things happen, anyway.

“It was important for me to set that tone defensively,” Capela said “I know most of the action is going to go through ‘big fella.’ Just challenge every catch and shot and make him work for every possession. Just make him work and wear him out.”

I like that plan. The Hawks should see if Embiid has it in him to beat them for a full game when they are making him grind.

Don’t overreact with help defense when Embiid gets the ball. Let Capela handle him for the most part. Force Embiid to bang his way to the basket or make spectacular plays away from it. If Embiid can do that for a full game, then give him credit for a great performance with a bad knee.

It’s a plan that admittedly could backfire. Embiid can defeat it through force of will, talent and intelligence. Great players can do that. There were moments in Game 4 when Embiid looked to have his usual bounce. He was ineffective on offense but still collected 21 rebounds

Embiid might rise again for Game 5. He will have only one day of rest between games, as opposed to two between games 3 and 4. But perhaps being back in Philadelphia will energize him. More motivation for Embiid, a master Twitter troll: He knows he will be clowned if the top-seeded Sixers are eliminated by the Hawks after leading the series 2-1.

Still, none of those factors will heal the torn cartilage in Embiid’s right knee.

“There are no excuses,” Embiid said. “I’ve got to do better.”

He’s right. Across the NBA playoffs, good teams are reeling because of injuries to star players. No one is giving those players or teams much sympathy. It’s bad luck for Embiid that he’s on that list, but he has a history of lower-body injuries, often the bane of NBA big men.

Embiid had right foot surgery before the 2014 draft and suffered complications from that procedure in 2015. His NBA debut was delayed until 2016-17. He lasted only 31 games that season before undergoing surgery to repair torn cartilage in his left knee.

Now torn cartilage in his other knee is the issue for Embiid. It didn’t seem to bother him much early in this series. It’s still possible Embiid will best the Hawks despite the injury. He couldn’t do it in Game 4. The Hawks should see if Embiid really has it in him to do it for the rest of the series.