With Jaylen Brown sidelined for the season after wrist surgery earlier this month, opportunities for Evan Fournier were expected to be plentiful heading into Boston’s first-round series against the Brooklyn Nets.

However, the veteran wing struggled to find consistent rhythm and opportunity in Game 1 at Barclays Center on Saturday. He struggled just like the rest of Boston’s offense against a small-ball Nets lineup that did plenty of switching. Fournier attempted just 10 shots over his 39 minutes of action, shooting a lackluster 30 percent from the field to finish with 10 points.

Brooklyn Nets forward Kevin Durant, left, reaches for the ball in front of Boston Celtics guard Evan Fournier during the second half of Game 1 of an NBA first-round playoff series Saturday, May 22, 2021, in New York. AP Photo/Corey Sipkin

After Monday’s practice in New York, Fournier acknowledged that the Celtics were pulled out of their own offensive flow a bit due to the Nets’ defensive tactics.

“Their switching is kind of disruptive,” Fournier said. “It throws you off-balance. The offense isn’t the same when the guys in front of you can switch 1 through 5. You can create some advantages with pin-downs, pick-and-rolls and all that, but when they switch, it kind of kills everything.”

Those switches led to plenty of isolations and low-pass possessions for the Celtics offense, producing just six assists and 40 points in the second half for the visitors. Brooklyn’s help defense and versatile lineup helped close down driving lanes and left several Celtics like Fournier as mere bystanders on possessions when they didn’t have the ball in their hands.

Improving that stagnant offense is a big point of emphasis heading to Game 2 for the Celtics, and it starts with a dynamic offensive threat in Fournier doing what he was acquired for after a midseason swap with Orlando.

“I have to do a better job at maybe creating more actions, having more energy on the floor and just be more available,” Fournier said. “So I watched the film and I’m going to try to do better things tomorrow night.”

Fournier has had a challenging start to his career in Boston on the heels of his diagnosis with COVID-19, which sidelined him for several weeks and impacted his play after his return due to the lingering symptoms. The ordeal has left the former Magic guard with limited time to find his rhythm with his new teammates in the final month of the regular season ahead of this series. Trying to find his place in an offense that desperately needs his help to keep pace with the Nets’ firepower is an ongoing struggle, but one that Fournier is determined to improve upon.

“Can I still play my best basketball even though I’m relatively new?” Fournier said. “Yes, no doubt. So like I said, it’s all on me; I have to do a better job finding my rhythm and finding opportunities within the offense and with the flow of the offense, maybe be more active on the boards so that we can push the ball in transition. Just find ways to help, you know?”

The Celtics have to make a big decision on the future unrestricted free agent this summer, as well, after Fournier was acquired with part of the team’s $28.5 million trade exception back in March. The team will have Bird Rights on him when free agency hits in August but a looming payroll crunch this offseason may force Danny Ainge to choose between re-signing Fournier and retaining other key members of the backcourt (Kemba Walker, Marcus Smart).

For that reason, Fournier’s play against an elite team in Brooklyn over the next two weeks is a crucial evaluation tool for the franchise. Boston’s roster may be far from whole, but the team needs to know whether Fournier can hold his own in a playoff setting as a key member of their supporting cast. That’s a role he has struggled with mightily in his career in Orlando during the postseason (10.0 PPG, 34.6% career shooter). If those struggles continue throughout the remainder of the series, it’s worth wondering whether the 28-year-old Frenchman is worth a hefty payday.

All of that will serve as a backdrop for Boston’s play in the series and makes Fournier very eager for a bounce back in Game 2 offensively for himself and the team.

“I think we played good defensively, and even the stretch defensively that we had where we just weren’t efficient,” he said. “We can learn from that and watch it and see why we weren’t good and get better Game 2. That’s the playoffs. That’s the part of playing through a playoff series. You learn from your mistakes, you try to do better things on defense and take the next game and make some adjustments and see where it goes.”

WILLIAMS EXPECTED FOR GAME 2

One of the biggest bright spots during the Celtics’ Game 1 loss to the Nets on Saturday was the play of Robert Williams III. The reserve center played through a turf toe injury that has sidelined him on and off for weeks and nearly posted a triple-double with a franchise-record nine blocks over his 23 minutes of action.

The Celtics were back at practice on Monday in preparation for Game 2 on Tuesday at the Barclays Center, and Williams is on track to play through the injury yet again in the matchup after logging big minutes on Saturday.

“Rob’s doing pretty well,” Brad Stevens said Monday. “We’re trying to keep him off his feet as much as possible on these days away from the game. But he was dressed and went through more of the walkthrough portion of practice. Should be ready to go tomorrow.”

Williams was a key component in the Celtics limiting the Nets to only 104 points on 41.7 percent shooting in Game 1, as he piled up his nine blocks in just about every way imaginable, from rejecting jump shots to recovery blocks at the rim. That dynamic play has put him on the Nets’ stars radar heading into Game 2.

“It’s impressive for just him making a huge impact on the game,” Brooklyn’s Kyrie Irving said of Williams after Game 1. “We’ll be more aware going into Game 2. He’s shifting over every single time on every one of our drives. So we just got to be a little bit smarter. But his timing is amazing.”

The biggest question for Boston as the series continues is just how much of a minute load Williams will be able to handle. He came off the bench in Game 1 to match up against Nic Claxton, but the Celtics were a far better team with him on the floor (plus-5) compared to Tristan Thompson (minus-16). Brad Stevens could try to hand Williams a bigger minutes load with a start in Game 2, but he runs the risk of aggravating the turf toe condition with a playing time increase.

“It’s going to be pain there, regardless; as much pain as you can take,” Williams said after Game 1. “When I’m out there, my adrenaline, the excitement of the game, kind of overtakes the pain, so I use that.”

No matter what the Celtics elect to do with the third-year center, Williams and his teammates will need to be locked in yet again defensively to have a chance of stealing Game 2.

“These guys are going to score, they’re gonna get to the money,” Williams said of the Nets. “Great offensive team. But we can’t get down on ourselves; we can’t get discouraged. In our heads we have to be ready to fight, fight back.”