Forget must-win. The Sixers are in a must-sweep situation with Celtics looming in Round 2.

All season, we’ve heard the Sixers talk about how much tougher they are. On Thursday, they’ll get a chance to prove it.

Win Game 3 on the road after taking a 2-0 series lead? That’s tough. Follow it up with another road win in Game 4? That’s tougher.

It’s also a necessity.

Anything other than a sweep is a loss. Even if it isn’t true, that has to be the mindset for the Sixers as they head to Brooklyn with a 2-0 lead. They are a team that is going to need every inch of advantage in the second round against the Celtics. In order to maximize that margin for error, they need to minimize the number of games it takes to dispatch the Nets. Win Game 3 on Thursday, end the series on Saturday, head back to the mothership to get ready for Boston.

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Most teams can afford a mulligan in a seven-game series against an overmatched opponent. The Sixers need to act as if they’ve already used theirs. Theirs came on Monday in the form of a brutal first half in which they scored just 44 points and turned the ball over 12 times. A lot of other teams would have blown them out of the gym. That the Nets didn’t was a favor. Now, the Sixers must capitalize.

“We got away with a half that was not how we play,” Sixers coach Doc Rivers said on Wednesday afternoon as his team prepared to depart for the bus trip up to Brooklyn. “But you’re not going to get away with it very often, so we have to be better.”

Last year, we saw what can happen when a superior team allows an opponent to hang around. After winning the first three games of their first-round series against the Raptors, the Sixers dropped Games 4 and 5 and then saw Joel Embiid suffer a concussion in Game 6. By the time the big man returned to the court in Game 3 of the conference semifinals, the Heat were two wins away from eliminating them.

Granted, injuries are just as liable to happen in Game 3 or Game 4 as they are in Games 5, 6, or 7. Even before Embiid took that blow to the head from Pascal Siakam at the end of Game 6, he’d already suffered a thumb injury that impacted his ability to shoot and might have hampered the Sixers in the following round. The year before, the Sixers were up, 3-0, on the Wizards when Embiid injured his knee in the first half of Game 4. For a team that is built around a singularly impactful player who regularly incurs singularly copious amounts of impact, bad things can happen at any time. But the fact remains: every additional game is an additional 48 minutes of risk incurred.

Besides, the benefits of a short series are greater than sheer probability. This is the Load Management Era. In the playoffs, there’s only one way to lighten one’s load. In each of the last three seasons, the eventual Eastern Conference champion has gotten to the second round in the minimum number of games. Last year, the Celtics’ first-round sweep of the Nets earned them five days of rest before a semifinals series against the Bucks that ended up going seven. Meanwhile, Milwaukee cost itself an extra two days of rest and preparation by losing to Chicago in Game 2 of its opening series.

Two years ago, when Milwaukee outlasted Brooklyn in the second round, it was the Bucks who were operating on an extra three days of rest after sweeping the Heat in the first round.

In both of those examples, it was the better-rested team that finished the series the strongest: Boston won three of the last four games against the Bucks in 2022, while Milwaukee won four of the last five against the Nets in 2021.

Did the extra rest actually make a difference? Who knows. But for this year’s Sixers, it can absolutely make a difference.

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“We can’t look ahead,” said Sixers guard Tyrese Maxey, who scored 33 points in Game 2 as the Sixers overcame a five-point halftime deficit to beat the Nets, 96-84, in Game 2. “We just talked about it, the next game up is the most important one. The main goal is to win four games. You always hope you can win them as quick as possible. Just get it done. That’s what we’re trying to do.”

There should be an extra level of urgency from the Sixers as they look across the Eastern Conference and see Boston cruising toward a quick ousting of the Hawks. The second-seeded Celtics have outscored Atlanta by a combined 42 points in the first halves of their first two wins in the series, with sixth-year guard Derrick White averaging 25 points on 18-of-29 shooting in Games 1 and 2. The Sixers are well aware of the dimension that White has brought to the Celtics since they acquired him at last year’s trade deadline. The last three times they’ve faced him this season, he’s averaged 21 points and a +12 plus/minus.

If they beat Boston, the Sixers will earn the right to do it all again against either Milwaukee or Miami. Together, those three teams represent the Eastern Conference’s last three NBA Finals participants, and two of the last three teams to knock the Sixers out of the playoffs.

That’s a tough road. Only one mindset will suffice. Win the battle and prepare for the real war.

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