Take it as a sign of their shiny new status as an Eastern Conference power player that the Nets can fumble their way through an entire half of basketball against a lesser opponent and still find a way to win, and win convincingly. Such was the case Sunday afternoon at Barclays Center, where the Nets rubbed the sleep out of their eyes in time to dismantle the short-handed Portland Trail Blazers, 98-85.

It took a second-half surge by the Nets, who improved to 8-4 overall and 6-1 at home. Joe Johnson scored a game-high 21 points as he shrugged off some early-season shooting woes, and Deron Williams finished with 15 points, 12 assists and a career-high four blocks.

If the Nets were looking past Portland, it was at least understandable. The game more or less set up as an appetizer for Monday's showdown with the visiting Knicks. Sure enough, Nets coach Avery Johnson removed his starters with 90 seconds left. The preparation had begun. "I know our guys are jacked up," Johnson said.

Joe Johnson, right, seems to be working out of his shooting funk. Getty Images

Things weren't so peachy against the Blazers (6-7), at least not early on. Portland found little resistance around the basket, even without center LaMarcus Aldridge, who missed the game with a stiff back. Johnson said he "visited" with his players at halftime.

"I told them I refuse to go crazy or use bad language," he said, "but I was really disappointed in our defense in the first half."

Williams had his own struggles, committing back-to-back turnovers late in the third quarter that led to transition buckets for Portland. Before the game, Johnson rattled off his star point guard's various maladies: bad hand, bad wrist, bad ankle, bad elbow. The list went on. His physical issues could be contributing to his trouble shooting the ball. He was 4 of 13 against the Blazers, and he has shot 33% from the field over his past six games.

Williams ratcheted up his energy in the fourth quarter, and his teammates responded, limiting Portland to 15 points. Johnson said his team played with a "sense of urgency" down the stretch.

He also credited the presence of forward Reggie Evans, who had another Reggie-esque stat line: 14 rebounds, two fouls, two points, 23 minutes. The league leader in rebounding efficiency, Evans said he was looking forward to Monday's game—because he looks forward to every game.

"This is my 11th year in the league," Evans said. "I've played the Knicks about 100 times. This is just another game, to be honest with you. I think it's big for a lot of people on the outside, but we approach it the same as usual. If we win, we're not going to be in the middle of the court celebrating, like, 'Oh! Oh!' We're not going to be popping no Champagne or nothing like that."

Write to Scott Cacciola at scott.cacciola@wsj.com