PHILADELPHIA — There was a nervous energy throughout the Wells Fargo Center on Saturday evening as the Philadelphia 76ers prepared to play Game 1 of their first-round playoff series against the Toronto Raptors.

The Sixers have star power that should overwhelm most other teams, but their stars have had trouble in the playoffs before. Joel Embiid, who led the N.B.A. in points per game during the regular season, has never been past the second round of the playoffs. James Harden, who won the league’s Most Valuable Player Award in 2017-18, has not been past the conference finals since he reached the N.B.A. finals with the Oklahoma City Thunder in 2012.

Did fans in the building dare hope that this team could win the franchise’s first championship since 1983?

Could Harden and Embiid come together quickly enough, despite having played only 21 regular-season games together?

The 76ers beat the Raptors, 131-111, avoiding the pitfalls that have ensnared them before against Toronto. They outrebounded the Raptors. They committed just one turnover in the game’s first 44 minutes. Game 1 offered hope.

But hope has its limits. If they are to prove that this group can succeed where past versions failed, the 76ers must build on Saturday night’s performance. The pressure on Embiid and Harden did not dissipate with the win.

“It’s only one game,” Embiid said, repeatedly, during his postgame news conference.

Embiid scored 19 points and grabbed 15 rebounds. Harden scored 22 points and had 14 assists. But the real star of the game for the 76ers was Tyrese Maxey, who scored 38 points, making 14 of his 21 shot attempts.

Late in the third quarter, Harden saw Maxey beating the Raptors down the court and grabbed the ball with both hands to throw Maxey a perfectly placed bounce pass that went nearly three-quarters the length of the court. Maxey caught it and scored with a reverse layup.

That play offered an example of the 21-year-old guard’s value to Philadelphia.

“He’s like the perfect player,” Harden said before commending Maxey’s ability to take advantage of times when he and Embiid drew multiple defenders.

Maxey couldn’t stop smiling as he checked out for the last time. He sat on the bench with the scoreboard camera fixed on him as the crowd chanted his name over and over. After the game, though, he didn’t bask in the adulation.

“The only thing I’m going to remember is us winning,” Maxey said. “That’s all that matters at this point. Now this is in my rearview mirror.”

The crowd erupted with what felt like a mixture of joy and relief — Philadelphia’s performance eased the tension in the building. But there remained an acute awareness that winning Game 1 does not mean you will win the series.

Harden knows what it is like to lose a series after winning its first game. In fact, it’s happened to him in the past two seasons. Last year, his Nets won Game 1 of a second-round series against Milwaukee before losing the series in seven games. Two years ago, his Rockets won Game 1 of a second-round series against the Lakers before losing the next four games.

Fair or not, this postseason will be the start of a referendum on the team that has been assembled in Philadelphia.

The Sixers replaced Ben Simmons, who was the first overall pick in the 2016 draft, with Harden in a trade in February.

Immediately after the trade, the 76ers started beating up on their opponents. They won the first game Harden played for them, beating the Minnesota Timberwolves by 31 points. Harden scored 27, and when he was in the game, the 76ers outscored the Timberwolves.

Philadelphia’s hiccups since Harden’s arrival, though, have been concerning. The Sixers lost to the Nets by 29 points in the first game between the teams since the trade. They lost twice to the Raptors in the final month of the season.

Simmons has not played for the Nets yet, but one could argue that the Nets are better poised to make a run in the playoffs than Philadelphia, despite being the seventh seed in the East, because of Kyrie Irving and the transcendent talent of Kevin Durant.

Harden was not particularly efficient against the Raptors on Saturday. He made 6 of 17 shots and only 2 of 10 2-pointers. He made his impact in assisting his teammates.

“I don’t think we’ve seen really what he can do,” Embiid said. “But he was comfortable tonight: made the right plays, found guys, went to the line a couple times even though they weren’t calling all his fouls for him. But it was good to see him aggressive.”

Coach Doc Rivers agreed that Harden seemed comfortable in the offense.

“You could tell. You could see it out there,” Rivers said. “He called plays himself.”

Rivers attributed that in part to his decision to simplify the team’s playbook and focus on the few plays he knew they could run well.

Maxey’s contributions were also critical to their plan. He sat on the podium next to Harden Saturday night and revealed a mischievous grin as Harden spoke about his postseason experiences.

“I’ve been in the playoffs 13 years,” Harden said.

Maxey interjected to call him old.

“Sorry,” Maxey said, as if he were a child caught misbehaving, before looking away and then smiling at the 32-year-old Harden again.

“I just wanted to play well,” Harden said. “I wanted to individually make sure I’m doing the right things, do what’s necessary for our team to win. Tonight I feel like individually I had an OK game, but that’s what you got a great team for.”

For Game 1 the 76ers got what they needed, but there’s no guarantee that the same formula will be enough as the playoffs progress — or even as this series moves to Game 2 on Monday.