Can the Sixers extend their season? That could rest on their ability to survive non-Joel Embiid minutes.

Joel Embiid acknowledged he did not feel in peak physical condition while playing the entire second half of Sunday’s Game 4 loss to the New York Knicks. But he also believed he needed to be on the floor for the entire 24 minutes.

“I felt like they always come back in the game in this series [when I’m on the bench],” Embiid said. “So I was like, I have nothing to lose, push myself.”

There are a multitude of reasons why the Sixers have slipped into a 3-1 hole in this first-round series, forcing a must-win Tuesday night at Madison Square Garden in order to keep their season alive. The rebounding. Jalen Brunson’s historic Game 4. Knicks role players hitting massive shots.

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But the statistical difference when Embiid is on the floor vs. off of it is drastic. The Sixers have a 34-point edge in the 159 minutes he has logged, and a 38-point deficit in the 33 minutes he has not. His absence effectively killed the Sixers’ momentum in at least Games 1 and 4, when leads quickly evaporated while he sat. And a ripple effect in Game 4 was Embiid’s visible fatigue after never sitting following halftime, potentially contributing to his one-point, one-rebound fourth quarter while primarily being guarded by the much smaller OG Anunoby.

“These games are all must-win, and we didn’t have a very good stretch when he was out in the first half,” Sixers coach Nick Nurse said after the game. “So we were willing to continue on.”

Though those on/off statistics are stark, they are not exactly stunning.

They first speak to the obvious on-court value of the reigning NBA Most Valuable Player, who dropped 50 points during Thursday’s Game 3 victory despite still recovering from knee surgery and dealing with a mild case of Bell’s palsy affecting the left side of his face.

Yet they are also a reminder of how much the Sixers struggled offensively while Embiid was sidelined for eight weeks. After ranking in the top five in the NBA in efficiency in November and December, the Sixers tumbled to the league’s bottom third in that category and field goal percentage in February and March. That is a big reason why the Sixers’ record was 11-22 from Jan. 24 through his return on April 2, sliding from third place in the Eastern Conference standings to seventh to set up this first-round matchup that likely would have occurred deeper in the playoffs had Embiid remained healthy.

The on/off discrepancy was most glaring to the Sixers in Game 1. After beginning the second quarter (when backup center Paul Reed entered for Embiid) with a 34-25 lead, the Knicks had pulled into a 40-40 tie by the time Embiid reentered less than five minutes later. Then when Embiid went to the locker room after aggravating his knee just before the break, a five-point Knicks lead rapidly swelled to 12.

Since then, Reed’s minutes have dwindled from 11:27 in Game 1 to 4:02 on Sunday — all during a second quarter when a 10-point Sixers lead shrank to five.

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Nurse has tinkered with other portions of the rotation during the past two games, most notably replacing Buddy Hield (whose outside shooting prowess should have made him an instant-offense, off-the-bench weapon) with Cameron Payne. Payne, however, could not replicate his eight-point second-quarter burst from Game 3, totaling five points in 13 minutes on Sunday.

That has also traditionally been a stretch in the game when Maxey has become the offense’s centerpiece; he has two double-digit second quarters in the series, but also went 2-of-9 from the floor in Game 1 and 1-of-4 in Game 3. It could also be an opening for Tobias Harris to provide some offensive pop, but he has not been a consistently reliable scoring option during this series.

It’s also a harsh reminder why president of basketball operations Daryl Morey publicly said he was coveting a backup center upgrade, but he did not acquire one by the February trade deadline.

“Obviously, when [Embiid is] out and when he’s in, our offense is kind of different,” Payne said. “But we’ve just got to find ways to stay aggressive and find a way to get good shots.”

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Nurse has established a reputation for playing his top guys heavy minutes. Before Embiid’s full second half Sunday, for instance, Maxey had done the same while battling illness during Game 2.

So in an actual must-win situation Tuesday, Embiid could very well flirt with logging the full 48. But extending their season beyond Game 5 might hinge on if the Sixers survive the MVP’s brief stretch on the bench.