ATLANTA — The 76ers have been here before.

Back in 2019, the Sixers lost to the Toronto Raptors in Game 1 of the Eastern Conference semifinals. They bounced back to win Games 2 and 3 to take a 2-1 lead in the best-of-seven series. They didn’t just win Game 3, they pummeled the Raptors, 116-95, on a night Joel Embiid had 33 points, 10 rebounds and five blocks.

With the Sixers seemingly in command of the series, the thought around Philly was that they were destined to reach the conference finals.

Instead, the Sixers went on to lose Game 4, 101-96, blowing a golden opportunity to put the Raptors on their heels by taking a commanding 3-1 lead.

Their 2019 NBA championship aspirations would eventually end on Kawhi Leonard’s 15-foot fadeaway jumper at the buzzer to lift the Raptors to the 92-90 victory in Game 7.

» READ MORE: Sixers’ size sapping Hawks’ strength

Fast forward to the Sixers’ current situation, facing the Atlanta Hawks in the conference semifinals. Philly holds a 2-1 series lead heading into Monday’s 7:30 p.m. Game 4 at State Farm Arena.

As it was against the Raptors, the Sixers lost Game 1 before bouncing back. They’ve posted 16-point victories in each of their two triumphs.

The Sixers have actually outscored the Hawks by 48 points in last the 10 quarters. And like in 2019, the thought, after the three games, is they’re destined to reach the conference finals. It’s just a matter of when they’ll closeout the series.

Just don’t tell that to Ben Simmons or perhaps any other Sixer.

“We can’t do that,” Simmons said of drifting into the thought of having the series locked up. “This is the playoffs. I mean, you saw it in Game 1 with us. We were down 26 [points] and we came back.

“Everyone is in the playoffs for a reason. This is a good team. So we can’t let up regardless if we are up 10 [points], 20, 30.”

That approach should advance them out of this round despite the loss of veteran leader Danny Green, who’s sidelined for at least 2-3 weeks with a Grade 2 strained right calf.

Deep at the guard and wing positions, coach Doc Rivers has several options to replace Green in the starting lineup. While he won’t be on the court, Green can still provide vocal leadership from the bench during timeouts and team gatherings.

So far, the Hawks have had a difficult time combating the Sixers’ length. At 6-foot-10, Simmons has a 9-inch height advantage on Hawks standout Trae Young, the player he’s guarded the past two games.

Matisse Thybulle, who’s also guarding Young, is 6-5 with a 6-11 wingspan.

There were a couple of times in Game 3 when Young was ready to shoot the ball but was forced to pass because a defender was right there to block or deflect it. And once he or other Hawks got into the lane, Joel Embiid (7-2) was there impeding their path to basket. So Embiid’s length and that of the Sixers’ perimeter defenders are creating problems.

Atlanta has also struggled mightilty from the three-point line in the past two games. They made a team playoff-record 20 in 47 attempts in their 128-124 Game 1 victory. Even that’s a bit misleading, considering they were 13-for-23 (56.5%) from three in the first half of Game 1 and are 24-for-77 (31.2%) since.

But the Hawks are finding three-point attempts tougher to get as the series progresses. They attempted 30 in Game 2 and 23 in Game 3. They only made six of their 23 (26.1%) attempts on Friday.

Their reduction in attempts the past two games has a lot to do with the Sixers’ concentration on eliminating open looks.

“There’s just a point of emphasis,” Thybulle said. “I think anyone who watched the first game saw how lackadaisical we came out in the first half. It’s hard to compare any of these games to the first game because the first half was so bad on our part, especially defensively. So it’s hard to say what we did. We are just playing a lot better. We are a lot more locked in.”

In regards to Young, the Sixers would rather give him the little floater in the lane than the three-point shot. The Sixers are also being aggressive with him in pick-and-rolls. As a result, he’s not getting a lot of looks.

One the other end, the Sixers are running a lot of pick-and-rolls and the Hawks don’t really want to switch. So the plays ends with Atlanta defenders getting picked off and chasing the Sixers instead of getting in front.

» READ MORE: Sixers small forward Danny Green to miss 2 to 5 weeks with Grade 2 right calf strain

Embiid is also taking advantage of the Hawks’ non-aggressive double-teams. He has routinely turned and looked for teammates, splitting the double-teams and drawing fouls.

Atlanta must be more aggressive on those double-teams, try to get Embiid in foul trouble, and try to wear him down with an up-and-down game.

The Sixers, however, have to keep doing what they’re doing while guarding against complacency. They can’t be satifised with winning one game on the away court. They must play with a killer instinct to win another game at State Farm Arena.

The Hawks’ road to success starts behind the three-point line. Except for the first half of Game 1, that road has been full of tall road blocks..